Synthesis of a robust multifunctional composite with concurrent magnetocaloric effect and enhanced energy absorption capabilities through a tailored processing route

Journal Pre-proof Synthesis of a robust multifunctional composite with concurrent magnetocaloric effect and enhanced energy absorption capabilities through a tailored processing route

Debottam Goswami, K.S. Anand, Parijat P. Jana, Sanjoy Kumar Ghorai, Santanu Chattopadhyay, Jayanta Das PII:

S0264-1275(19)30837-8

DOI:

https://doi.org/10.1016/j.matdes.2019.108399

Reference:

JMADE 108399

To appear in:

Materials & Design

Received date:

10 August 2019

Revised date:

29 November 2019

Accepted date:

2 December 2019

Please cite this article as: D. Goswami, K.S. Anand, P.P. Jana, et al., Synthesis of a robust multifunctional composite with concurrent magnetocaloric effect and enhanced energy absorption capabilities through a tailored processing route, Materials & Design(2019), https://doi.org/10.1016/j.matdes.2019.108399

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

© 2019 Published by Elsevier.

Journal Pre-proof

Synthesis of a robust multifunctional composite with concurrent magnetocaloric effect and enhanced energy absorption capabilities through a tailored processing route Debottam Goswami1, K.S. Anand3, Parijat P. Jana3, Sanjoy Kumar Ghorai2, Santanu Chattopadhyay1, 2 , Jayanta Das1, 3* 1

School of Nano-science and Technology, Indian Institute of Technology Kharagpur, Kharagpur 721 302, West Bengal, India. 2

Rubber Technology Center, Indian Institute of Technology Kharagpur, Kharagpur 721 302, West Bengal, India. 3

ro

of

Department of Metallurgical and Materials Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721 302, West Bengal, India.

-p

ABSTRACT

We report the synthesis and characterization of a multifunctional composite obtained by

re

integrating micron-sized Ni52Mn26Ga22 Heusler alloy particles into a polysulfone matrix. The

lP

Heusler alloy powders were synthesized by the ball milling of as-spun Ni52Mn26Ga22 ribbons and subsequently incorporated into a polysulfone matrix using the solution casting process. The microstructural, magnetic and thermomechanical properties of the alloy-polymer

na

composites were investigated. X-ray diffraction and transmission electron microscopy analyses revealed the presence of a 14M modulated crystal structure along with a hierarchical

ur

twinning system down to the atomic scale. Magneto-metric and thermomechanical testing

Jo

revealed that the prepared composite demonstrates a magnetocaloric effect with a usable refrigeration capacity of 3.1 J/kg under a moderate magnetic field change of 1.38 T as well as a wideband energy absorption capability at a low 5 wt.% loading. The disadvantages of bulk Ni-Mn-Ga single crystals such as inherent brittleness and difficulty of production may be overcome by the incorporation of micro-size particles into a flexible polymer matrix without compromising with its functional properties. Our work demonstrates a tailored processing route to obtain multifunctional composites for possible applications in spot cooling and broadband energy absorption. Keywords: Transmission electron microscopy (TEM), Nanotwinning, Multifunctional composites, Magnetetocaloric effect, Thermomechanical properties *Corresponding author: Tel.: +91 3222 283284; fax: +91 3222 282280; E-mail: [email protected]

1

Journal Pre-proof 1. Introduction In the last two decades, a lot of research activity led to the development of the multifunctional Ni-Mn-X [X = Ga, Sn, Al, In, Sb] Heusler alloy systems demonstrating some interesting properties such as, giant magnetocaloric effect (GMCE), elastocaloric effect (ECE), magnetic field induced strain (MFIS) as well as energy damping via twin boundary motion [1-6]. Among the several Heusler alloy systems, the Ni-Mn-Ga alloys were studied by many groups due to its low cost, easy tunability and the multiferroic effects arising from the magneto-structural transformation from the low-temperature ferromagnetic martensite to the high-temperature paramagnetic austenite phase [7,8]. However, single crystals and some

of

polycrystalline forms of Ni-Mn-Ga are inherently brittle which render them difficult to shape

ro

and form thus posing a major drawback towards their application. Heusler alloy – polymer hybrid composite materials, therefore, were proposed as an expedient substitute [9-13]. The

-p

class of Heusler alloy-polymer composites have been investigated for possible applications in magneto-actuation, magnetic field induced strain, and energy absorption [11,12,16], however

re

the soft magnetic properties and the magnetocaloric aspect have been rarely studied. The

lP

prime objective of the present study is to synthesize a composite demonstrating a significant magnetocaloric effect along with an added functionality i.e. energy damping.

isothermal entropy change (

na

The pre-requisite for any material to act as a magnetocaloric regenerator are a large ), a high refrigeration capacity (RC) value and low thermal

ur

losses during operation. Studies have shown that precise compositional tuning and processing can render the magnetocaloric performance of some alloys in the Ni-Mn-Ga system close to

Jo

the benchmark values of Gd5Si2Ge2 and LaFeSi [14]. Moreover, some compositions in the Ni-Mn-Ga alloy system display a twinned microstructure characteristic of a modulated martensite phase (14M/10M). These martensite variants/twin boundaries display a hierarchical nature across an increasing length scale of observation. The higher-order mesoscale twin variants are very mobile, their movement and the friction between the variant interfaces dissipate a considerable amount of energy when the material is externally stressed. Consequently, the damping capability of the martensite phase particularly in the magnetostructural transformation temperature range is high [15]. Many researchers have demonstrated the presence of these mobile, mechanically activated twin boundaries in NiMn-Ga under dynamic, [16] and static loading [17]. Moreover, some previous studies of NiMn-Ga – polymer composite systems by Lahelin et al. [18] and Feuchtwanger et al. [19] have shown that the Heusler alloy ribbons/powders/micro-wires incorporated into epoxy

2

Journal Pre-proof hysol/silicone matrices may be successfully used as energy damping materials. Therefore, an opportunity exists that a multifunctional composite may be designed if a precisely tuned Heusler alloy is integrated within a suitable polymer matrix. A matrix system such as epoxy is not very flexible and is prone to cracking at high filler loadings, [20] limiting their applications in constricted spaces. The matrix needs to be selected such that it is thin and flexible while having a large interaction area to maximize heat flow and reduce losses. However, it should simultaneously be strong enough for a long service life. Polysulfone is a flexible specialty polymer, possessing high thermal, oxidative and hydrolytic stability. The presence of the diphenylene-sulfone group in the polymer chain not

of

only provides thermal stability but also high strength, high resistance to oxidation, and

ro

excellent flame retardant properties to this class of engineering polymers [21]. Polysulfone based composites can be fabricated as flexible thin sheets or films. This is beneficial during

-p

their application as active heat exchanger materials since thin films would inherently incur lower losses during heat transfer in and out of the media. Since the magnetostructural

re

transition in Heusler alloys leads to concurrent caloric effects as well as energy absorption in

lP

its vicinity, suitably tailored alloy particles which have a pronounced magnetostructural transition and mechanically activated twin boundaries may be reinforced in a polysulfone

na

matrix to obtain a multifunctional composite.

The first order magneto-structural transformation drives a large

value and

ur

possesses inherent irreversibility, which leads to hysteresis and thermal losses during thermal/magnetic cycling between the phases [22]. Usually, the hysteresis and thermal losses

Jo

during the first-order transition occur due to the formation and movement of phase boundaries, which act as energy barriers. [23]. Thus the hysteresis and associated losses in the filler particles present in the polysulfone matrix must be reduced for the optimum utilization of the composite as a magnetocaloric material. This may be achieved following different approaches such as altering the chemical composition or by the introduction of defects whereby the nucleation barrier is decreased [23,24]. Recently, it was also demonstrated that a reduction in hysteresis and improvement in the refrigeration capacity (RC) of Heusler alloys could be achieved by grinding bulk alloys into microparticles [25]. However, in our case, the reduction of the transformation hysteresis and increment of the RC value is required without affecting the twinned microstructure during processing

3

Journal Pre-proof To produce particles which, have a twinned microstructure, low transformation hysteresis and, a large refrigeration capacity (RC), we have adopted a low energy ball milling process. Ni52Mn26Ga22 (at.%) as spun ribbons (ASR) were prepared by melt spinning, which were milled to obtain micro-sized particles and denoted as ball milled powder (BMP). The Ni52Mn26Ga22 was chosen due to its large isothermal entropy change (

), high RC value

and a twinned microstructure [26]. The low energy ball milling ensures that the microstructure of the ribbons is retained while the average particle size is reduced to the micrometer regime thereby enhancing the interaction surface area. The BMPs were incorporated into polysulfone by solution casting to obtain the alloy-polymer composite

of

(APC) with 2.5 wt.% and 5 wt.% loadings (denoted henceforth as APC2.5 and APC5).

ro

During the cure, no external magnetic field was applied. Tian et.al had reported that the damping effect in disordered composites was higher than that observed in the composites

-p

where the filler particles were aligned by an external magnetic field. Such effect was observed in the vicinity of the Tg of the matrix [27]. Hence, disordered composites were

re

produced which possess enhanced damping effect as well as reduced processing complexity. The ASR, BMP and the APC samples show isothermal entropy change values (

) of -

lP

2.85, - 1.1 and - 0.14 J/kg/K, respectively, for an external field change of 1.38 T. The ball milling process lead to a desirable enhancement of refrigerant capacity (RC) in the BMP

na

sample. Thermo-mechanical testing of the composite revealed promising damping capabilities due to the mechanically induced twin boundary motion of the Ni-Mn-Ga particles

ur

in the polysulfone matrix. The effect of the structural transitions on the evolution of tanδ

Jo

peaks and the damping behavior of the composite sample has also been investigated. 2. Materials and experimental methods 2.1 Materials and processing methods A polycrystalline ingot of 10 g having a nominal composition Ni52 Mn26Ga22 (at.%) was prepared using an arc-melter in an argon atmosphere by co-melting high purity (99.9 %) Ni, Mn and Ga elements with 1 at. % extra Mn to compensate for its loss during melting. The ingot was flipped and was remelted at least five times to achieve homogeneity. After that, the ingots were sectioned and were analyzed by EDS for compositional verification. The ingot was then induction melted and the liquid melt was ejected into a water-cooled copper wheel rotating at a wheel speed of 845 rpm i.e., wheel surface speed of 15 m/s to achieve ribbons using a melt spinner. The Ar-gas overpressure was 0.24 MPa during melt spinning. The

4

Journal Pre-proof dimensions of the as melt-spun ribbons were 90-100 mm in length, 6 mm in width and 80-90 µm thick. The obtained ribbons were sealed in a hardened steel vial under argon atmosphere for 1 h dry ball milling using Retch planetary ball mill PM 400 MA with a ball to powder ratio (BPR) of 20:1 for a 15 min run and 10 min pause. To relieve the stresses introduced during ball milling, the obtained powders were sealed in a quartz tube under vacuum and were heat-treated at 973 K for 24 h followed by air cooling to room temperature. The polymer – alloy micro-particle composite film was prepared using high purity polysulfone supplied by Sigma Aldrich, (USA). At first, 0.6 g of polysulfone was dissolved into tetrahydrofuran (THF) by stirring. Then 0.030 g of alloy powder was mixed with the solution

of

by mechanical stirring. The slurry was gently poured into a PTFE mold and then the cast was

ro

cured at room temperature without the influence of an external magnetic field. Proper care was taken during casting to prevent trapping of any air bubbles. The resulting film is a

-p

composite having a uniform thickness of ~ 0.2 mm and comprised of polysulfone-5 wt.% of Ni-Mn-Ga (APC5) micro-sized alloy particles. A similar process was adopted to synthesize a

re

2.5 wt% film (APC2.5) as well as a pure polysulfone film to compare the functional

2.2 Characterization methods

lP

properties.

na

The microstructural imaging and composition analysis were performed using a Zeiss Merlin field-emission scanning electron microscope (FESEM) attached with an EDAX -

ur

Octane energy dispersive x-ray spectrometer (EDS). Transmission electron microscopy (TEM) analyses of the ASR and BMP were performed in an FEI Tecnai G2 20 microscope

Jo

operating at 200 kV. High-resolution transmission electron microscopy (HRTEM) of the BMP sample was performed in a JEOL JEM 2100F field emission microscope equipped with a Gatan 4K CMOS camera, operating at 200 kV. The ASR was thinned down to 40 µm by manual polishing followed by ion milling using a Gatan PIPS system to obtain the required sample specifications for TEM analyses. The BMP sample was prepared for TEM by dropcasting a suspension of the alloy microparticles in ethanol onto a carbon-coated Cu grid. The thermal characterization of the samples was done using a Perkin Elmer 8000 differential scanning calorimeter (DSC) calorimeter at a heating rate of 20 K/min, to identify the onset of the phase transformation temperatures in the samples as well as the thermal stability. Phase and crystallographic information were investigated using an XPert Pro diffractometer using the Cu Kα radiation in the range of 2θ = 30 – 120° in Bragg Brentano geometry. The refinement of the powder diffraction data was done according to the Rietveld model, using 5

Journal Pre-proof the Fullprof suite [28]. Magnetic properties were investigated using a Lakeshore Cryotronics 7410 vibrating sample magnetometer (VSM). To investigate the magnetization versus temperature (M-T) characteristics, the sample was heated from room temperature (300 K) up to 390 K without any external magnetic field and then the data was recorded in the cooling sequence (FC) from 390 K to 250 K where the externally applied field was 100 Oe. Similarly, the data was recorded in the heating sequence (FH) where the sample was heated from 250 K to 390 K just after the FC sequence. Isothermal magnetization curves (M-H) were recorded within a temperature interval of 5 K while cooling from 390 K to 290 K and varying the field from 0 T to 1.38 T. The soft magnetic properties of the APC2.5 and APC5 samples were

of

investigated for measuring fields up to ± 2 T at room temperature (300 K). The thermomechanical testing was carried out in a dynamic mechanical analyzer (DMA, Perkin Elmer

ro

8000) in the tension mode and the shear mode of an Anton – Paar MCR 102 rheometer for a

-p

sinusoidal shearing frequency of 1 Hz. The heating rate for both the instruments was fixed at

re

3 K/min. 3. Results and discussion

lP

3.1 Physical characteristics and microstructure

na

The photograph of APC5 is depicted in Fig. 1. Evidently, the alloy fillers are distributed in a heterogeneous manner within the polymer matrix as viewed in the

ur

macroscale. Inset of Fig. 1 demonstrates that the prepared composite is flexible and has a low thickness. No evidence of crack formation or any macro-deformation of the composite after

Jo

bending, has been revealed.

Figure 1: Photographs of APC5 specimen showing the heterogeneous filler distribution. Inset: Large flexibility in the APC without cracking.

6

Journal Pre-proof The bulk composition of the ASR sample has been estimated using an EDS detector attached to a FESEM at 500X magnification. The composition was measured at 5 different regions of the specimen, which was estimated to be Ni52.20±0.58Mn25.50±0.85Ga22.71±0.55. The EDS results indicate that Mn depletion has occurred possibly during the melt spinning, as the nominal composition was Ni52Mn26Ga22. The BSE image of the ASR sample reveals the distinct martensitic laths within the prior austenite grains as depicted in Fig. 2(a). The presence of micro-twins along with the absence of macro-twins defines the microstructure, which is a characteristic of a modulated martensitic phase. The morphology and distribution of the alloy powders (BMP) are shown in Fig. 2(b) pointing towards the evolution of irregular

of

and flaky shaped particles. The mean size of these particles has been estimated by the circle

ro

equivalent diameter as measured from the FESEM secondary electron (SE) images and were found to be in the range of 15 to 18 µm. However, few much smaller particles having a

-p

particle size in the nanometer scale were also produced which were revealed in the TEM micrographs. These flaky particles show typical characteristics of brittle fracture of the

re

ribbons and localized welding during the milling process due to the evolution of new surfaces on each particle. Fig. 2(d) depicts a higher magnification image of a single alloy micro-

lP

particle, which reveals the presence of multiple grains having irregular morphology within it. The average grain size of irregular grains in BMP specimen was estimated from the FESEM

na

micrographs using the line intercept method. The analysis was performed on five micrographs using ten equidistant horizontal lines resulting an average grain size of 220±20

ur

nm. The SE image of APC5 is depicted in Fig. 2(e). The cross-section of the composite sample after cryo-fracture as observed in the BSE mode is represented in Fig. 2(f). The

Jo

presence of the alloy particles across the cross-section, having similar morphology as the ball-milled powders in the polymeric matrix is evident.

7

Journal Pre-proof Figure 2: SEM micrographs of (a) ASR sample revealing the presence of fine micro-twins as observed in the SE imaging mode, (b) SE image of the BMP showing the flaky morphology of the particles, (c) Particle size histogram revealing the mean particle size, (d) High magnification SE image of a single micro-particle revealing the presence of individual grains within it, (e) SE image of the APC revealing the brighter alloy particle in the dark polysulfone matrix, and (f) BSE image of the constituent phases in APC sample after cryofracture. 3.2 X-ray diffraction studies The x-ray diffraction (XRD) patterns of the ASR, BMP and APC5 specimens collected at room temperature are shown in Fig. 3(a). The reflections obtained from the ASR

of

sample revealed the presence of a modulated (14M) martensite structure and satellites are indexed in the inset of Fig. 3(a). Rietveld refinement of the profile revealed the presence of a

ro

tenfold superstructure having a monoclinic unit cell belonging to the space group P 2/m, as depicted in Fig. 3(b). The cell parameters were found to be a = 4.254±0.001Å, b =

-p

5.498±0.001Å, c = 42.120±0.002Å and β= 93.38±0.01°. The refinement of the XRD pattern

re

of BMP sample (Fig. 3(c)) also revealed the presence of a monoclinic unit cell with P 2/m space group and cell parameters a = 4.253±0.001Å, b = 5.500±0.001Å, c = 42.111±0.003Å

lP

and β = 93.35±0.01°. The crystallite size was measured to be 66±1 nm for the ASR and 52±1 nm for the BMP samples, respectively The refined parameters have been summarized in

na

Table 1.These results are in agreement with that present in literature for polycrystalline Ni-

Jo

ur

Mn-Ga and rapidly solidified Ni-Mn-In ribbons [29,30].

Figure 3: (a) XRD patterns of the ASR, BMP and APC5 samples showing the presence of satellite peaks of monoclinic 14M martensite (P 2/m) in ASR and BMP specimens. A broad halo can be observed in APC5 due to the large fraction of amorphous polysulfone matrix. Refinement of the XRD patterns of the (b) ASR and (c) BMP showing the observed, calculated and difference curves.

8

Journal Pre-proof The XRD analyses reveal that both the ASR and the BMP samples possess modulated martensite structures. The modulated (14M) martensite structure in the ASR is a consequence of the internal stresses during rapid solidification [31]. Furthermore, the XRD analyses also revealed that the milling process caused the mere fragmentation of the brittle ribbons. However, the process induces strain into the unit cell, which changes the lattice parameters. Therefore, lattice parameter-dependent values of the TC and the equilibrium martensitic transformation temperatures are altered. The XRD pattern of the APC5 sample shows a broad hump near the major reflections of the 14M martensite phase of the alloy particles present in

its amorphous structure.

ro

3.3 High-resolution transmission electron microscopy

of

the matrix. No sharp diffraction peaks from the polysulfone matrix have been noticed due to

Fig. 4(a) shows the HRTEM image of the BMP confirming the presence of nano-

-p

twins along with stacking faults to match the product martensite lattice to the parent

re

austenite. The formation of these nano-twins and the modulated martensite may be understood by the concept of adaptive martensite forming from austenite by diffusionless

lP

transformation. The transformation from a cubic austenite lattice (A) to a tetragonal nonmodulated (NM) martensite structure proceeds by the movement of the habit plane. However,

na

twinning is necessary to reduce the elastic strain energy developed during the transformation. The lattice misfit at the habit plane is accommodated by the alternate arrangement of the

ur

tetragonal unit cells of the NM martensite, which results in twinning at the phase boundary [32,33]. A cubic unit cell may be distorted to a tetragonal unit by elongation of any of the 3

Jo

equivalent axes. Two of such differently orientated tetragonal martensitic unit cells are separated by a twin boundary. Along this direction, Khachaturyan et al. have suggested the concept of adaptive martensitic structure, where a reduction of the twin boundary spacing to the atomic scale is required when the elastic strain energy dominates over the twin boundary energy [34]. The above concept explains the evolution of the modulated structure in martensite phase resulting in the formation of nano-twinned microstructure. The 14M modulated martensite consists of alternating tetragonal NM unit cells having ( ⁄ ) Twin boundaries are observed every 2 long ( ) and 5 short ( ̅ ) planes, where ̅ , tetragonal building blocks having different orientations. If

.

are the

̅ the unit cell attains a

monoclinic distortion. In the Zhdanov’s notation, this periodic stacking is denoted as ( ̅ ) , thus ( ̅ ) for 7M/14M modulated structure. The periodic stacking is therefore ( ̅ ) for a 5M/10M modulated structure [35]. The modulation in 10/14M martensite is an 9

Journal Pre-proof incommensurate one i.e., the atoms deviate from their ideal position by a scattering vector q [28]. Furthermore, the modulated martensite is a metastable state and may proceed to a lower energy state with a tetragonal NM structure by twin boundary annihilation and coarsening. Fig. 4(a) provides the direct evidence of such ( ̅ ) stacking sequence at the atomic level of the martensitic phase in the region adjoining the habit plane, as marked by the green line. The HRTEM image also reveals that the ( ̅ ) stacking does not show any inversion symmetry. Moreover, the retained austenite (A) on the right of the habit plane possesses a cubic structure. The presence of monoclinic distortion in the unit cell of the 14M martensite

of

structure has been confirmed by the x-ray diffraction studies. The nano-twin boundaries are also referred to as the primary twin boundaries, which are marked by red lines in Fig. 4(a).

ro

Such primary nano-twin boundaries exhibit low mobility in response to external magnetic fields, as reported earlier [36]. Therefore, mobile twin boundaries/ interfaces should exist in

-p

the 14M modulated martensite phase, which can explain the large strains exhibited under

Jo

ur

na

lP

re

external stress/magnetic fields.

Figure 4: (a) HRTEM image of BMP showing the primary nano-twins, their boundaries and the habit plane at the interface between martensite (M) and retained austenite (A). (b) TEM BF image of an alloy particle revealing the presence of mesoscale twin boundaries in the BMP, and (c) TEM BF image of the ASR showing mesoscale twin boundaries constraining the growth of the primary twin variants. The mesoscale twin boundaries are comprised of differently aligned 14M nano-twin variants as shown in Fig. 4(b) for BMP specimen. These mesoscale twin lamellae exhibit a larger thickness of ~51 nm than the nano-twins of ~1.4 nm thickness. Therefore, the spacing between two mesoscale twin boundaries is much wider as compared to the nanotwin boundaries which form between the alternating tetragonal unit cells [32]. Similar mesoscale boundaries are also observed in the ASR, as marked in Fig. 4(c). These mesoscale boundaries are mobile under external magnetic fields or stress [32,37] compared to the nanotwin

10

Journal Pre-proof boundaries. Their mobility may be attributed to a diffuse nature rather than being atomically sharp. The electron micrograph of the BMP also reveals the presence of the mesoscale boundaries within the single alloy particle. Fig. 4(b) confirms that the adopted processing route retains the twinned microstructure in the BMP, which should be ideal for energy absorption in the APCs due to the presence of mobile mesoscale twin boundaries. 3.3 Thermal studies The DSC heat flow curves of the ASR and BMP samples have been shown in Fig. 5. The exothermic and endothermic peaks represent the forward austenite to martensite and the

of

reverse martensite to austenite transformations, respectively. The transformation temperatures of the above transformations have been estimated by the tangent method and the results are

ro

summarized in Table 2. Here, As, Af correspond to the austenite start and finish temperatures is

-p

and Ms, Mf corresponds to the martensite start and finish temperatures, respectively.

the equilibrium temperature of martensitic transformation which has been calculated )

[31]. The enthalpy change (ΔH) for the reverse

re

(

according to the formula:

transformations is estimated to be 7.7, 6.09 J/Kg for the ASR, BMP samples, respectively.

lP

The lower value of ΔH for the BMP sample indicates a lower volume fraction of the austenite transforming into martensite after ball milling. The

of the BMP sample has also

na

decreased by 4 K compared to the ASR, which may be attributed to the destabilization of the martensite phase and a reduction of the internal stresses in the BMP than that of the ASR.

ur

The heat flow curves of the APC5 and APC2.5 samples displayed similar endothermic maxima during the heating cycle with a noticeable shift of 9K of the characteristic

Jo

transformation temperatures due to the presence of the polysulfone matrix.

Figure 5: DSC curves of the ASR and BMP samples showing the structural transformation during heating and cooling cycles. The onset of As and Af during the heating and Ms, Mf temperatures during cooling are marked.

11

Journal Pre-proof 3.4 Magnetization studies The temperature-dependent magnetization (M-T) curves of the ASR, BMP, and APC5 samples are plotted in Fig. 6(a). for a 100 Oe measuring field. On cooling from 390 K all the samples show a characteristic transition from paramagnetic (PM) austenite to ferromagnetic (FM) martensite. The magnetic moment increases with a decrease in temperature which indicates that the spins cohesively align to increase the magnetization. The magnetization of the BMP sample is observed to be lower than that of the ASR sample by a factor of 0.28. The TC of the samples was determined as a minimum on the temperature derivative of the

of

magnetization curve (dM/dT) [38] (plot for the APC5 sample is shown in the inset of Fig. 6(b)). It was observed that the TC for all the samples lied below the Ms in the FC curve.

ro

Hence, it is intuitive that the parent austenite phase is paramagnetic and ferromagnetism is observed only after a phase transition to the product martensite. The TC is thus represented as

-p

the TCm which is at 357, 353, and 354 K for the ASR, BMP and APC5 respectively. A close

re

similarity between the normalized FC curves of the BMP and APC5 during transformation indicates that the polymer matrix has a negligible contribution to the M-T behavior of the

Jo

ur

na

lP

composite sample.

Figure 6. Magnetization versus temperature (M-T) plots of (a) ASR, BMP, APC5 samples during field cooling (FC) cycle revealing a characteristic paramagnetic to ferromagnetic transition. (b) M-T plot of the APC5 sample during FH and FC. Inset to Fig. 6 (b) represents the dM/dT plot to estimate the value of TC.

12

Journal Pre-proof The TCm value decreased from 357 K in the ASR sample to 353 K upon ball milling. Such a decrease in the TCm can be attributed due to the weakening of the FM correlations of the Mn atoms in the Heusler lattice. A systematic study of the Ni-Mn-Ga showed that the interatomic distances, the lattice parameter, and the electronic orbital overlap had played an important role in the magnitude and the direction of the exchange energy in the martensite phase as well as during its structural transition [39]. A direct correlation between the lattice parameters and the TC was also observed more recently by us in Fe-Ni based alloys [40]. In a Ni-Mn-Ga Heusler unit cell with a monoclinic distortion, the Mn atoms are located on the 1a, 1d and the 2m, 2n Wykoff sites respectively [28]. The FM exchange arises due to the

of

coupling between the spins of the Mn atoms in the two adjacent unit cells. Any displacement

ro

of the atomic positions in the unit cells during cold working weakens the ferromagnetic exchange or may turn it into an antiferromagnetic (AFM) one. The XRD analyses had

-p

revealed that ball milling introduced a change in the lattice parameters of the monoclinic unit cell of the ASR. The lattice parameters a and c have decreased while the parameter b has

re

increased. Such an alteration in the adjacent positioning of the Mn atoms results in the dilution in the magnetic subsystem and consequently lowers the TCm as well as the

lP

magnetization value of the FM martensite in the BMP sample. It may be observed in the FC and FH curves of the APC5 that the reversible transitions from the FM martensite to PM

na

austenite display a thermal hysteresis of 14 K which is the characteristic of a first-order transformation [41, 42]. However, a second-order transition may contribute such hysteresis as

ur

well between the FH and FC curves since the VSM instrument measures the temperature of the sample chamber and not directly of the sample [42]. In the case of the APC5 sample, the

Jo

particles embedded in the polymer matrix have a longer thermal response time which results in even a larger hysteresis than that of the individual constituents. Therefore, the application of the Banerjee’s criterion to the Arrott plots should be more suitable in this scenario to identify the true nature of the magnetic transitions. The virgin loop process was used for the M-H measurements of all the samples under an increasing magnetic field from 0 to 1.38 T. Data was recorded during cooling from 390 K to 330 K in steps of 5 K. The Arrott plots derived from the M-H curves of the BMP and ASR samples are shown in Figs. 7(a,b). A positive slope in M2 versus H/M curves represents a second-order magnetic transition which may be observed in the case of the BMP sample, as shown in Fig. 7(a). Whereas, the curves for the ASR sample shows a negative slope near the TC, which indicate the first-order transition in the sample [37,43]. Since the BMP acts as the

13

Journal Pre-proof filler in the APC samples, it is intuitive that the magnetic transitions occurring in the APC5 are also of a second order. The M-H curves across the FM to PM transition of the APC5 sample as depicted in Fig. 7(c) display a sharp increase in magnetization followed by a change into progressive increments characteristic of magnetic saturation. The room temperature M-H loop of the APC5 sample as depicted in Fig. 7(d) reveals excellent soft magnetic behavior with coercivity (

) = 103.60 Oe. The observed magnetization value (

)

is 2.61 emu/g for H = 2 T. It should be noted that the APC2.5 sample shows negligible

ur

na

lP

re

-p

ro

of

response in the M-H measurements for fields up to 2T (not shown here).

Jo

Figure 7: (a,b) Arrott plots for the BMP and ASR samples showing the nature of the magnetic transitions, (c) M-H plots of the APC5 during cooling from 390 K used to calculate the entropy change and (d) Major M-H loop of the APC5 at room temperature revealing its soft magnetic properties. Inset to Fig. 7 (d) represents the coercive area of the M-H loop of the APC5 sample.

3.5 Magnetocaloric effect The magnetocaloric properties of the samples have been determined from the isothermal magnetization curves M-H by first heating the samples to a temperature well above TC to erase the magnetic memory and then cooled in zero field to the intended temperature before starting measurements. Such a method eradicates any spurious higher values of

arising due to the measurement technique [42]. The entropy change

been calculated using a numerical approximation of Maxwell’s formula,

14

has

Journal Pre-proof ( )

∫ (

)

,

(1)

where M is the magnetization when the applied field is H at a temperature T [26,41]. The values of maximum entropy change

max

calculated for the ASR, BMP and the APC5

samples are - 2.85, - 1.1 and - 0.14 J/kg/K respectively for a moderate ΔH of 1.38 T. Usually, a first-order transition results in a sharp staggered peak in the

versus temperature plot

whereas a broad peak denotes a second-order transition [42]. The nature of the

(T)

curves in Fig. 8 correlate well with the Arrott plots as shown in Figs. 7(a,b) confirming that the ball milling process results in the domination of the second-order phase transition over the

ro

of

first.

-p

Figure 8: Magnetic entropy change

versus

re

T curves for the ASR, BMP and APC5

na

lP

samples.

The refrigerant capacity (RC), of a material is another fundamental criterion used to

ur

evaluate the magnetocaloric performance of a material. The value of RC estimates the amount of thermal energy that can be transferred by a refrigerant between the hot and cold

Jo

reservoirs in one ideal thermodynamic cycle [41] and has been calculated according to the formula, RC =

max

.δTFWHM

(2)

where, δTFWHM is the full width at half maximum of the

(T) peak, as depicted in Fig. 8

[41]. The calculated values of δTFWHM are 6.6 K, 21.01 K, and 22.2 K, and the value of RC for the ASR, BMP and the APC5 samples are 18.81 J/kg, 21.01 J/kg and 3.1 J/kg, respectively. The synergistic coupling between the first-order structural transition with the secondorder magnetic transition usually leads to a beneficial high value of

Such a coupling is

usually detected when TC ≈ Teq as observed in the case of Ni-Mn-Ga system for a specific

15

Journal Pre-proof composition range as well as in other ferromagnetic alloy systems such as Ni-Fe-Ga and CoNi-Ga systems [44, 45]. However, in the case of the BMP sample, the value of ΔT = (TC–Teq) is 5 K, which must be a result of well disengaged first and second-order transitions. Although the milling process leads to a lower peak value of

, it leads to an enhanced working

interval (δTFWHM) and therefore an increased RC value of 21.01 J/kg in the BMPs as compared to that of the ASR with RC of 18.81 J/kg. Such enhancement of RC value in Heusler alloy powder upon ball milling is consistent with that reported by Qian et al. [25]. Even though, the mechanical properties of a magnetocaloric La-Fe-Si alloy powderthermoplastic composite was studied by Lanzarini et al., but the value of

or RC of the

of

composite was not reported [46]. On the other hand, the APC5 sample has exhibited RC

ro

value of 3.1 J/kg. Therefore, the synthesized composite is a promising candidate for its possible use in biological applications demanding an immediate spot cooling, in future lab-

-p

on-chip setups for an energy-efficient cooling solution or even as building blocks for

re

complex regenerators for next-generation magnetic refrigeration devices [47]. 3.6 Thermomechanical testing and vibration damping measurements

lP

3.6.1 Storage modulus (E’) and loss modulus (E”)

na

The response of the composite samples was measured in the linear viscoelastic region for an applied 5 Hz sinusoidal and 1 Hz shearing stress respectively. Fig. 9(a) represents the

ur

behavior of the storage modulus (E’) and the loss modulus (E”) which are the real and imaginary parts of the complex modulus during testing in the tension mode. The storage and

Jo

the loss moduli represent the elastic and viscous behavior of a viscoelastic sample [48]. It was observed that the values of E’ for both the APC5 and APC2.5 samples exhibited a gradual decrease till temperatures ~ 350K. The value of E’ for the APC5 undergoes a considerable decrease after 360 K, which is the As point (Table 2) of the magnetostructural transformation in the fillers (BMP). However, in the case of the APC2.5, the values of E’ exhibited this nature after 390 K. This transition may be attributed to the glass transition event at the glass transition temperature (Tg) of the polysulfone matrix in case of the APC2.5 sample. The glass transition temperature is the point at which amorphous polymers change from the glassy to the rubbery state owing to enhanced mobility of the molecular segments with an associated increase in the free volume. This transition in the APC2.5 is however, dissociable to the magnetostructural transformation in the APC5 as evident by the different temperature regimes of transformation. The values of E’’ versus T 16

Journal Pre-proof also exhibited a similar nature where, the E’’ peak is observed at 368 K; the region of the magnetostructural transition in case of the APC5. Whereas, the E’’ peak is observed at 391 K which is near the Tg in the case of the APC2.5. Customarily, a maximum in the E’’ value of a polymer is observed at the Tg where the movements of the molecular segments initialize, resulting in high internal friction. A high E’’ value indicates a high viscous response and thus a high energy dissipation capability [48]. Since the E’’ maxima in the APC5 is greater than that of APC2.5, therefore the magnetostructural transformation can be effectively exploited for an enhanced energy damping effect. Furthermore, it may be deduced that a 2.5 wt% loading is deficient to harvest the magnetostructural transformation thus, the APC2.5 shows

ro

3.6.2 Energy damping (tanδ) and Cole-Cole plots

of

characteristics similar to that of a pure polysulfone film of similar thickness.

-p

The loss ratio (tangent) tanδ; which is a measure of the phase angle between the stress and sample strain during periodic excitation of the APCs in the tension mode is

re

depicted in Fig. 9(b). The values of tan δ can be used as a measure of the energy dissipative

lP

capabilities of a material [50]. It is observed that the values of tan δ remain nearly constant until ~ 350 K. This trend of the tan δ values up to 350 K must be attributed to the two

na

dissipative mechanisms. First, the dissipative effects at the alloy/polymer interface and the second the dissipative effect due to the twin boundary movement inside the alloy particles.

ur

The obtained results are consistent with that of reported by Lahelin et al. and Glock et al. [18,36] for Ni-Mn-Ga powder – polymer and Ni-Mn-Ga wire – epoxy composites. A

Jo

considerable increase in the value of tan δ for the APC5 is noticeable at temperature above 350 K as the martensitic transforms into austenite phase. Thus, the damping effect increases upon heating up to ~ 382 K, and decreases after that with the completion of the transformation at 383 K. The tanδ peak as observed at Af, is consistent with the reports of Glock et al. and Sun et al. [36,51]. The value of tan δ is 0.29 for the APC5, which is nearly identical with that of epoxy-17 wt.% NiMnGa composite (tan δ = 0.30), as reported by Tian et. al [27]. A second peak in the loss ratio has been observed at ~ 406 K in APCs due to the Tg of the polysulfone matrix. Since the glass transition and the martensitic transformation events are separated and resolvable, it is intuitive that the APC5 can be utilized efficiently as a broadband damping material. The value of tanδ corresponding to the magnetostructural transition subdues the values arising from the glass transition event of the matrix, as evident

17

Journal Pre-proof in Fig. 9(b). The positions of the maxima agree well to behavior of E’’ versus temperature for

re

-p

ro

of

both the APC2.5 and APC5.

ur

na

lP

Figure 9: (a) Storage modulus (E’) and Loss modulus (E’’) versus temperature for APC2.5 and APC5 samples. (b) tan δ versus temperature for the composites revealing distinct maxima due to the magnetostructural transition and glass transition. (c) The Cole-Cole plots of the samples revealing the distribution and filler-matrix interaction for both of the samples; the semi-elliptical and semi-circular shapes have been superimposed on the data plots, and (d) storage modulus (E’) and tan δ versus temperature for the APC5 for a shearing frequency of 1 Hz.

Jo

Cole-Cole plots of the composites have been plotted to reveal the nature of dispersion and the filler matrix interaction in the composites. It has been reported that a smooth, semicircular arc denotes a homogenous system containing well-dispersed fillers. On the other hand, semi-elliptical curves denote a heterogeneous system with imperfect distribution [47,52]. The different states of dispersion of the filler particles in the 2.5 and 5 wt.% composites are evident by the broader and narrower arcs. As depicted in Fig. 9(c), the plot of the APC5 is semi-elliptical denoting a macroscopically heterogeneous system that agrees well with the photograph depicted in Fig. 1. On the other hand, the plot of the APC2.5 is more of a semicircular nature indicating a better dispersion. This behavior is expected as the filler loading percentage of the APC2.5 is lesser leading to lower phase segregation within the composite as compared to the APC5. The semi-elliptical nature of the Cole-Cole plots, however also denotes better interaction between the filler particles and the matrix [51].

18

Journal Pre-proof Furthermore, the behavior of the APC5 sample during shearing (Fig. 9(d)) is similar to that in the tension mode, where two separate resolvable peaks have been identified as well due to the magnetostructural and the glass transition events. As the magnetostructural transformation of the particles occurred at a lower temperature than the glass transition event of the matrix, the APC5 retains its desirable properties such as stiffness and form at the temperature corresponding to the tanδmax. Therefore, the synthesized APCs can be employed in applications safely up to 390 K without any loss of the mechanical characteristics while providing efficient damping in either tensile or shearing based applications.

of

4. Conclusions. A multifunctional composite has been synthesized by incorporating the ball-milled

ro

Ni52Mn26Ga22 powders into a polysulfone matrix to explore the magnetic and structural



-p

properties. The key findings have been summarized as follows:

Powders with a flaky and irregular morphology having micrometer size distribution were

re

produced by ball milling of the as-spun ribbons. The ASR and BMP both possess mobile twin boundaries, as revealed by HRTEM analyses. The milling process has decreased the TCm and the Teq values of the BMP sample by 4 K

lP



as compared to the ASR sample but has increased the value of RC by 2.2 J/Kg. The APC5 has exhibited the

peak at ~ 367 K arising due to the synergistic effects of

na



the magnetocaloric and structural transition from martensite to austenite. The thermomechanical testing of the APC5 exhibits two distinct tan δ maxima as

ur



Jo

identified due to the magnetostructural and the glass transition events, which is advantageous for the application of the composite as a broadband damper in both tensile and shearing based application requirements. 

A minimum filler loading of 5 wt.% is essential to obtain an enhanced damping capability over the pure polysulfone

Acknowledgments The authors thank S. Maity at the Central Research Facility at IIT Kharagpur for technical assistance. Financial support by Sponsored Research and Industrial Consultancy (SRIC), IIT Kharagpur through SGBSI is gratefully acknowledged. Credit author statement J.D. conceived the project. JD, SC, and DG designed the experiments. DG performed the experiments and wrote the manuscript. All authors discussed the results and commented on the manuscript.

19

Journal Pre-proof References

Jo

ur

na

lP

re

-p

ro

of

1. F. Hu, B. Shen, J. Sun, Magnetic entropy change in Ni51.5Mn22.7Ga25.8 alloy, Appl. Phys. Lett. 76 (2000) 3460–3462, doi:10.1063/1.126677. 2. H. Zhang, M. Qian, X. Zhang, S. Jiang, L. Wei, D. Xing, J. Sun, L. Geng, Magnetocaloric effect of Ni-Fe-Mn-Sn microwires prepared by melt-extraction technique, Mater. Des. 114 (2017) 1–9, doi:https://doi.org/10.1016/j.matdes.2016.10.077. 3. Z. Yang, D.Y. Cong, L. Huang, Z.H. Nie, X.M. Sun, Q.H. Zhang, Y.D. Wang, Large elastocaloric effect in a Ni–Co–Mn–Sn magnetic shape memory alloy, Mater. Des. 92 (2016) 932–936, doi:https://doi.org/10.1016/j.matdes.2015.12.118. 4. A. Sozinov, A.A. Likhachev, N. Lanska, K. Ullakko, Giant magnetic-field-induced strain in NiMnGa seven-layered martensitic phase, Appl. Phys. Lett. 80 (2002) 1746– 1748, doi:10.1063/1.1458075. 5. M. Chmielus, X.X. Zhang, C. Witherspoon, D.C. Dunand, P. Müllner, Giant magnetic-field-induced strains in polycrystalline Ni–Mn–Ga foams, Nat. Mater. 8 (2009) 863, https://doi.org/10.1038/nmat2527. 6. I. Aaltio, M. Lahelin, O. Söderberg, O. Heczko, B. Löfgren, Y. Ge, J. Seppälä, S.P. Hannula, Temperature dependence of the damping properties of Ni-Mn-Ga alloys, Mater. Sci. Eng. A. (2008), doi:10.1016/j.msea.2006.12.229. 7. M. Pasquale, C.P. Sasso, L.H. Lewis, L. Giudici, T. Lograsso, D. Schlagel, Magnetostructural transition and magnetocaloric effect in Ni55Mn20Ga25 single crystals, Phys. Rev. B. 72 (2005) 94435, doi:10.1103/PhysRevB.72.094435. 8. T. Krenke, E. Duman, M. Acet, E.F. Wassermann, X. Moya, L. Mañosa, A. Planes, Inverse magnetocaloric effect in ferromagnetic Ni–Mn–Sn alloys, Nat. Mater. 4 (2005) 450–454, doi:10.1038/nmat1395. 9. J. Raghavan, T. Bartkiewicz, S. Boyko, M. Kupriyanov, N. Rajapakse, B. Yu, Damping, tensile, and impact properties of superelastic shape memory alloy (SMA) fiber-reinforced polymer composites, Compos. Part B Eng. 41 (2010) 214–222, doi:https://doi.org/10.1016/j.compositesb.2009.10.009. 10. D.M. Liu, Z.H. Nie, G. Wang, Y.D. Wang, D.E. Brown, J. Pearson, P.K. Liaw, Y. Ren, In-situ studies of stress- and magnetic-field-induced phase transformation in a polymer-bonded Ni-Co-Mn-In composite, Mater. Sci. Eng. A. 527 (2010) 3561–3571, doi:10.1016/j.msea.2010.02.034. 11. S. Glock, L.P. Canal, C.M. Grize, V. Michaud, Magneto-mechanical actuation of ferromagnetic shape memory alloy/epoxy composites, Compos. Sci. Technol. 114 (2015) 110-118, doi:10.1016/j.compscitech.2015.04.009. 12. F. Nilsén, I. Aaltio, S.P. Hannula, Comparison of magnetic field controlled damping properties of single crystal Ni-Mn-Ga and Ni-Mn-Ga polymer hybrid composite structures, Compos. Sci. Technol. 160 (2018) 138-144, doi:10.1016/j.compscitech.2018.03.026. 13. S. Kauffmann-Weiss, N. Scheerbaum, J. Liu, H. Klauss, L. Schultz, E. Mäder, R. Häßler, G. Heinrich, O. Gutfleisch, Reversible Magnetic Field Induced Strain in Ni2MnGa-Polymer-Composites, Adv. Eng. Mater. 14 (2012) 20–27, doi:10.1002/adem.201100128. 14. L. Pareti, M. Solzi, F. Albertini, A. Paoluzi, Giant entropy change at the cooccurrence of structural and magnetic transitions in the Ni Mn Ga Heusler alloy, Eur. Phys. J. B - Condens. Matter Complex Syst. 32 (2003) 303–307, doi:10.1140/epjb/e2003-00102-y.

20

Journal Pre-proof

Jo

ur

na

lP

re

-p

ro

of

15. I. Aaltio, K.P. Mohanchandra, O. Heczko, M. Lahelin, Y. Ge, G.P. Carman, O. Söderberg, B. Löfgren, J. Seppälä, S.P. Hannula, Temperature dependence of mechanical damping in Ni-Mn-Ga austenite and non-modulated martensite, Scr. Mater. 59 (2008) 550-553, doi:10.1016/j.scriptamat.2008.05.005. 16. J. Feuchtwanger, S. Michael, J. Juang, D. Bono, R.C. O’Handley, S.M. Allen, C. Jenkins, J. Goldie, A. Berkowitz, Energy absorption in Ni-Mn-Ga-polymer composites, J. Appl. Phys. 93 (2003) 8528–8530, doi:10.1063/1.1557762. 17. S. Conti, M. Lenz, M. Rumpf, Macroscopic behaviour of magnetic shape-memory polycrystals and polymer composites, Mater. Sci. Eng. A. 481–482 (2008) 351–355, doi:10.1016/j.msea.2007.04.126. 18. J. Feuchtwanger, E. Seif, P. Sratongon, H. Hosoda, V.A. Chernenko, Vibration damping of Ni-Mn-Ga/silicone composites, Scr. Mater. 146 (2018) 9–12, doi:10.1016/j.scriptamat.2017.10.028. 19. M. Lahelin, I. Aaltio, O. Heczko, O. Söderberg, Y. Ge, B. Löfgren, S.P. Hannula, J. Seppälä, DMA testing of Ni-Mn-Ga/polymer composites, Compos. Part A Appl. Sci. Manuf. 40 (2009) 125-129, doi:10.1016/j.compositesa.2008.10.011. 20. L. Wei, H. Yu, L. Yufeng, Y. Naibin, Damping of Ni-Mn-Ga epoxy resin composites, Chinese J. Aeronaut. 26 (2013) 1596, doi:10.1016/j.cja.2013.10.005. 21. J. Drobny, Properties of polysulfone. In Specialty Thermoplastics. Springer, Berlin, Heidelberg (2015) 110-113, doi: 10.1007/978-3-662-46419-9 22. T. Gottschall, K.P. Skokov, R. Burriel, O. Gutfleisch, On the S(T) diagram of magnetocaloric materials with first-order transition: Kinetic and cyclic effects of Heusler alloys, Acta Mater. 107 (2016) 1–8, doi:10.1016/j.actamat.2016.01.052. 23. R. Niemann, S. Hahn, A. Diestel, A. Backen, L. Schultz, K. Nielsch, M.F.-X. Wagner, S. Fähler, Reducing the nucleation barrier in magnetocaloric Heusler alloys by nanoindentation, APL Mater. 4 (2016) 64101, doi:10.1063/1.4943289. 24. M. Trassinelli, M. Marangolo, M. Eddrief, V.H. Etgens, V. Gafton, S. Hidki, E. Lacaze, E. Lamour, C. Prigent, J.-P. Rozet, S. Steydli, Y. Zheng, D. Vernhet, Suppression of the thermal hysteresis in magnetocaloric MnAs thin film by highly charged ion bombardment, Appl. Phys. Lett. 104 (2014) 81906, doi:10.1063/1.4866663. 25. M. Qian, X. Zhang, Z. Jia, X. Wan, L. Geng, Enhanced magnetic refrigeration capacity in Ni-Mn-Ga micro-particles, Mater. Des. 148 (2018) 115–123, doi:10.1016/j.matdes.2018.03.062. 26. Z.B. Li, J.L. Sánchez Llamazares, C.F. Sánchez-Valdés, Y.D. Zhang, C. Esling, X. Zhao, L. Zuo, Microstructure and magnetocaloric effect of melt-spun Ni 52 Mn 26 Ga 22 ribbon, Appl. Phys. Lett. 100 (2012) 174102, doi:10.1063/1.4704780. 27. B. Tian, F. Chen, Y. Tong, L. Li, Y. Zheng, Magnetic field induced strain and damping behavior of Ni-Mn-Ga particles/epoxy resin composite, J. Alloys Compd. 604 (2014) 137–141, doi:10.1016/j.jallcom.2014.03.100. 28. J. Rodriguez-Carvajal, Physica B. 192 (1993) 55-69. https://doi.org/10.1016/09214526(93)90108-I. 29. L. Righi, F. Albertini, E. Villa, A. Paoluzi, G. Calestani, V. Chernenko, S. Besseghini, C. Ritter, F. Passaretti, Crystal structure of 7M modulated Ni-Mn-Ga martensitic phase, Acta Mater. 56 (2008) 4529–4535, doi:10.1016/j.actamat.2008.05.010. 30. W. Maziarz, A. Wójcik, P. Czaja, A. Zywczak, J. Dutkiewicz, Ł. Hawełek, E. Cesari, Magneto-structural transformations in Ni50Mn37.5Sn12.5-xInx Heusler powders, J. Magn. Magn. Mater. 412 (2016) 123–131, doi:10.1016/j.jmmm.2016.03.089.

21

Journal Pre-proof

Jo

ur

na

lP

re

-p

ro

of

31. S. Glock, X.X. Zhang, N.J. Kucza, P. Müllner, V. Michaud, Structural, physical and damping properties of melt-spun Ni-Mn-Ga wire-epoxy composites, Compos. Part A Appl. Sci. Manuf. 63 (2014) 68–75, doi:10.1016/j.compositesa.2014.04.005. 32. S. Kaufmann, R. Niemann, T. Thersleff, U.K. Róßler, O. Heczko, J. Buschbeck, B. Holzapfel, L. Schultz, S. Fáhler, Modulated martensite: Why it forms and why it deforms easily, New J. Phys. 13 (2011) 053029, doi:10.1088/1367-2630/13/5/053029. 33. M.E. Gruner, R. Niemann, P. Entel, R. Pentcheva, U.K. Rößler, K. Nielsch, S. Fähler, Modulations in martensitic Heusler alloys originate from nanotwin ordering, Sci. Rep. 8 (2018) 8489, doi:10.1038/s41598-018-26652-6. 34. A.G. Khachaturyan, S.M. Shapiro, S. Semenovskaya, Adaptive phase formation in martensitic transformation, Phys. Rev. B. 43 (1991) 10832–10843, doi:10.1103/PhysRevB.43.10832. 35. R. Chulist, L. Straka, H. Seiner, A. Sozinov, N. Schell, T. Tokarski, Branching of {110) twin boundaries in five-layered Ni-Mn-Ga bent single crystals, Mater. Des. 171 (2019) 107703, doi:https://doi.org/10.1016/j.matdes.2019.107703. 36. O. Söderberg, L. Straka, V. Novák, O. Heczko, S.-P. Hannula, V.K. Lindroos, Tensile/compressive behaviour of non-layered tetragonal Ni52.8Mn25.7Ga21.5 alloy, Mater. Sci. Eng. A. 386 (2004) 27–33, doi:https://doi.org/10.1016/j.msea.2004.07.045. 37. H. Seiner, L. Straka, O. Heczko, A microstructural model of motion of macro-twin interfaces in Ni-Mn-Ga 10 M martensite, J. Mech. Phys. Solids. 64 (2014) 198–211, doi:10.1016/j.jmps.2013.11.004. 38. B. Uthaman, K.S. Anand, R.K. Rajan, H.H. Kyaw, S. Thomas, S. Al-Harthi, K.G. Suresh, M.R. Varma, Structural properties, magnetic interactions, magnetocaloric effect and critical behaviour of cobalt doped La 0.7 Te 0.3 MnO 3, RSC Adv. 5 (2015) 86144–86155, doi:10.1039/c5ra13408k. 39. V. V. Khovailo, V. Novosad, T. Takagi, D.A. Filippov, R.Z. Levitin, A.N. Vasil’ev, Magnetic properties and magnetostructural phase transitions in Ni 2+x Mn 1-x Ga shape memory alloys, Phys. Rev. B - Condens. Matter Mater. Phys. 70 (2004) 1–6, doi:10.1103/PhysRevB.70.174413. 40. K.S. Anand, D. Goswami, P.P. Jana, J. Das, Correlating the lattice parameter and Curie temperature of γ-Ni in Fe-Ni-base alloys, AIP Adv. 9 (2019) 55126, doi:10.1063/1.5097345. 41. K.S. Anand, P.P. Jana, D. Prabhu, J. Das, The effect of milling time on the evolution of nanostructure, thermal stability, and magnetocaloric properties of (Ni0.50Fe0.50)70.5B17.7Si7.8Ti4, J. Alloys Compd. (2019) 157-163, doi:10.1016/j.jallcom.2018.09.074. 42. V. Franco, K. Skokov, D.Y. Karpenkov, O. Gutfleisch, I. Radulov, A. Conde, J.Y. Law, V. Brabander, Predicting the tricritical point composition of a series of LaFeSi magnetocaloric alloys via universal scaling, J. Phys. D. Appl. Phys. 50 (2017) 414004, doi:10.1088/1361-6463/aa8792. 43. B.K. Banerjee, On a generalised approach to first and second order magnetic transitions, Phys. Lett. 12 (1964) 16–17, doi:10.1016/0031-9163(64)91158-8. 44. K. Oikawa, T. Ota, T. Ohmori, Y. Tanaka, H. Morito, A. Fujita, R. Kainuma, K. Fukamichi, K. Ishida, Magnetic and martensitic phase transitions in ferromagnetic Ni–Ga–Fe shape memory alloys, Appl. Phys. Lett. 81 (2002) 5201–5203, doi:10.1063/1.1532105. 45. V. V. Khovaylo, V.D. Buchelnikov, R. Kainuma, V. V. Koledov, M. Ohtsuka, V.G. Shavrov, T. Takagi, S. V. Taskaev, A.N. Vasiliev, Phase transitions in Ni2+xMn1-

22

Journal Pre-proof

Jo

ur

na

lP

re

-p

ro

of

xGa with a high Ni excess, Phys. Rev. B - Condens. Matter Mater. Phys. 72 (2005) 1– 10, doi:10.1103/PhysRevB.72.224408. 46. J. Lanzarini, T. Barriere, M. Sahli, J.C. Gelin, A. Dubrez, C. Mayer, M. Pierronnet, P. Vikner, Thermoplastic filled with magnetocaloric powder, Mater. Des. 87 (2015) 1022–1029. doi:https://doi.org/10.1016/j.matdes.2015.08.057. 47. V. Franco, J.S. Blázquez, B. Ingale, A. Conde, The Magnetocaloric Effect and Magnetic Refrigeration Near Room Temperature: Materials and Models, Annu. Rev. Mater. Res. 42 (2012) 305–342, doi:10.1146/annurev-matsci-062910-100356. 48. S.S. Chee, M. Jawaid, M.T.H. Sultan, O.Y. Alothman, L.C. Abdullah, Thermomechanical and dynamic mechanical properties of bamboo/woven kenaf mat reinforced epoxy hybrid composites, Compos. Part B Eng. 163 (2019) 165–174, doi:10.1016/J.COMPOSITESB.2018.11.039. 49. N. Saba, A. Safwan, M.L. Sanyang, F. Mohammad, M. Pervaiz, M. Jawaid, O.Y. Alothman, M. Sain, Thermal and dynamic mechanical properties of cellulose nanofibers reinforced epoxy composites, Int. J. Biol. Macromol. 102 (2017) 822–828, doi:10.1016/J.IJBIOMAC.2017.04.074. 50. W. Obande, D. Mamalis, D. Ray, L. Yang, C.M. Ó Brádaigh, Mechanical and thermomechanical characterisation of vacuum-infused thermoplastic- and thermosetbased composites, Mater. Des. 175 (2019) 107828, doi:https://doi.org/10.1016/j.matdes.2019.107828. 51. X.G. Sun, C.Y. Xie, Damping characteristics of a NiMnGa/polymer composite material, Mater. Sci. Forum 561 (2007) 697-699, doi:https://doi.org/10.4028/www.scientific.net/MSF.561-565.697 52. P.V. Joseph, G. Mathew, K. Joseph, G. Groeninckx, S. Thomas, Dynamic mechanical properties of short sisal fibre reinforced polypropylene composites, Compos. Part A Appl. Sci. Manuf. 34 (2003) 275–290, doi:10.1016/S1359-835X(02)00020-9.

23

Journal Pre-proof Table 1: Structural parameters of the 14M martensite phase in ASR and BMP samples. ASR

BMP P 2/m

P 2/m

a (Å)

4.254±0.001

4.253±0.001

b (Å)

5.498±0.001

5.500±0.001

c (Å)

42.120±0.002

42.111±0.003

0

93.35±0.010

983.20

983.21

6.38

4.29

Space group

β

93.38±0.01

Volume (Å3)

ro

of

Rwp (%)

Table 2: Characteristic temperatures of the magneto-structural transitions as obtained from

-p

M-T curves at 10 K/min and DSC thermograms at 20 K/min during the heating and cooling

re

cycles of ASR, BMP, and APC5 samples.

Thermal studies

Ms(K) Mf(K) TC(K)

As(K) Af(K)

Ms(K)

Mf(K)

Tm(K)

ASR

340

365

359

347

357

359

368

358

345

352

BMP

359

383

366

345

353

354

378

366

342

348

APC5 359

384

359

354

365

375

-

-

-

ur

343

: Transition temperatures not prominent during cooling.

Jo

-

lP

As(K) Af(K)

na

Magnetic studies

24

Journal Pre-proof CRediT author statement

Jo

ur

na

lP

re

-p

ro

of

J.D. conceived the project. JD, SC, and DG designed the experiments. DG performed the experiments and wrote the manuscript. All authors discussed the results and commented on the manuscript.

25

Journal Pre-proof

Jo

ur

na

lP

re

-p

ro

of

Graphical abstract

26

Journal Pre-proof Highlights 1. Micron-size Heusler alloy particles were produced by ball milling of rapidly quenched ribbons. 2. The ribbons and milled powders possess modulated martensite structure comprised of immobile nano-twins and mobile mesoscale twins. 3. The alloy particles were incorporated into a flexible polysulfone matrix in order to

of

produce a multifunctional composite.

ro

4. The composite shows good magnetocaloric effect along with vibration damping

Jo

ur

na

lP

re

-p

capabilities.

27