Influence of microelement Hf on microstructure, mechanical properties and shielding effect of W-Ni-Fe alloy

Accepted Manuscript Influence of microelement Hf on microstructure, mechanical properties and shielding effect of W-Ni-Fe alloy Tang Dewen, Shuliang Zou, Yan Liang PII:

S0925-8388(17)32392-7

DOI:

10.1016/j.jallcom.2017.07.037

Reference:

JALCOM 42453

To appear in:

Journal of Alloys and Compounds

Received Date: 29 April 2017 Revised Date:

20 June 2017

Accepted Date: 5 July 2017

Please cite this article as: T. Dewen, S. Zou, Y. Liang, Influence of microelement Hf on microstructure, mechanical properties and shielding effect of W-Ni-Fe alloy, Journal of Alloys and Compounds (2017), doi: 10.1016/j.jallcom.2017.07.037. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. 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.

ACCEPTED MANUSCRIPT

Influence

of

Microelement

Hf

on

Microstructure,

Mechanical Properties and Shielding Effect of W-Ni-Fe Alloy Tang Dewen

a, b**

, Zou Shuliangb, Yan Lianga

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(a School of mechanical engineering, University of South China, Hunan, Hengyang, 421001) ( Hunan Provincial Key Laboratory of Emergency Safety Technology and Equipment for Nuclear b

Facilities, University of South China, Hunan, Hengyang, 421001)

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Abstract: W-Ni-Fe-Hf series alloy with different Hf contents were prepared through liquid phase sintering. Influences of Hf on mechanical properties, shielding effect and microstructure of W-Ni-Fe-Hf alloy are analyzed and discussed by using SEM, XRD

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device, metalloscope, BH1326 γ-ray shield tester and so on. The results of the study show that adding the microelement Hf could increase dispersity of powder effectively. Hf distributes in the binding phase of W-Ni-Fe-Hf series alloy (percentage) as an intermediate phase. This intermediate phase not only could refine crystals, but also has good affinity to the microelement Hf, thus enabling to improve mechanical

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properties and shielding effect of the alloy. However, the intermediate phase formed by excessive Hf is easy to cause segregation on the interface between W crystal boundaries and Ni-Fe binding phase, which would weaken interface binding strength and thereby deteriorate mechanical properties of the alloy.

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Key words: Ni-Fe-Hf alloy, Microelement Hf, Microstructure, Mechanical properties,

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Shielding effect

*Corresponding

author:

Tang

Dewen;

Tel./

Fax:

0734-8282242,

E-mail:

ACCEPTED MANUSCRIPT [email protected] 1. Introduction W-Ni-Fe alloy with high density, high strength, good ductility, small coefficient of thermal expansion and strong γ-ray absorption capacity has attracted high attentions [1]

. Due to its excellent mechanical properties and shielding

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in recent years

performance, W-Ni-Fe alloy is widely used in various fields, such as electronic information, medical aid, aerospace, nuclear industry, etc. Shielding protection of materials and devices which are sensitive to radiation is an effective way to improve reliability of electronic system in nuclear environment. Lead (Pb) is a common γ-ray

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shielding material, but it has some disadvantages, including toxicity, poor high temperature resistance and low mechanical strength. W-Ni-Fe alloy has high

Pb

[2-3]

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mechanical strength and can shield various rays, which makes it a good substitution of . However, since multi-phase structure and solid solution of W-Ni-Fe alloy

form a nonequilibrium character, the formation of new phases is often accompanied with pores and spaces, which restrict application and development of W-Ni-Fe series alloy significantly.

According to recent researches in China and foreign countries, grain refinement

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can improve both mechanical properties and shielding performance of alloys[4-6]. Reinforced sintering involving micro-nanometer processing of raw powders and grain growth inhibitor is an effective mean to prepare fine W alloys[7-9]. Lin et al.[10]

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established the Pb-Fe and Fe-Pb models, finding that heavy-light element combination is superior to light-heavy element combination. Zhang et al.

[11]

compared shielding performances of W-Ni alloys and the influence of the Ni content

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through experiment. He pointed out that the γ-ray absorption capacity of W-Ni alloys is significantly higher than that of the traditional shielding material (Pb). Moreover, to achieve same shielding effect, thickness of W-Ni alloys is only 2/3 of that of Pb. prepared W-B polyethylene compound. Bose et al. found that with the increase of W and B4C contents, the compound achieves higher shielding effect, tensile strength and elasticity modulus, and thought that B and C elements may refine material structure by adding refractory metals (e.g. Mo, Hf and Re)

[12]

. A lot of researches on

refinement of alloy structure by adding rare earth oxide have been reported in the past years. But they pointed out that adding HfO2, Y2O3 and La2O3 could inhibit W crystal expansion during the sintering effectively

[13-16]

. But excessive microelements would

ACCEPTED MANUSCRIPT weaken interface binding strength when refining the structure, finally causing insignificant improvement of mechanical properties and shielding effect of the alloy. Therefore, in this paper, W-Ni-Fe-Hf series alloy with different Hf contents (%) are prepared through liquid phase sintering by using W, Ni and Fe elementary powders, which have been processed by ball milling, high-pressure forming, and

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compaction and sintering. Influences of Hf contents (mass fraction: 0.3%, 0.6%, 0.9%, 1.2% and 1.5%) on mechanical properties, shielding effect and microstructure of W-Ni-Fe-Hf series alloy are analyzed 2. Test method

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W, Ni, Fe and Hf elementary powders are used to prepare high density, high strength, good ductility and shielding effect W-Ni-Fe-Hf series alloy. Their physical and chemical properties and impurity contents are presented in Table 1 and Table 2.

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Test devices: W-Ni-Fe-Hf series alloys were prepared in a vacuum medium-frequency induction sintering furnace (model: ZG-0.01L) with the characteristics of quickly heating rate, uniform heating, few auxiliary equipment and easy control. The maximum temperature can reach over 1873K. Technical conditions of liquid phase sintering: In vacuum conditions, the

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W-Ni-Fe-Hf series alloys mixed at a certain proportion were sintered under 1753K at heating rate of 30K/min. The liquid phase sintering was set 30 min, followed by furnace cooling. The parameters of liquid phase sintering are listed in Table 3. Sample preparation: W, Ni, Fe and Hf elementary powders were grinded and

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refined using a planetary ball mill. During the grinding appropriate amount of ethyl alcohol was added as a wet-grinding medium to make them mix evenly. The mixture

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was dried in an electro-thermal blowing dry box to get rid of the wet-grinding medium. The mixed powder preparation technology and parameters is displayed in Table 4. W-Ni-Fe-Hf series alloy mixing powder was shaped in a steel die with a hydraulic single column press. The preparations of samples are presented in Table 3. Volumes of sintered samples were tested by using drainage measuring method.

Sintered samples of mass was measured by the Bs210s electronic scales (accuracy: 0.1mg), which was used to measure density of W-Ni-Fe-Hf series alloy. Micro-hardness

of

W-Ni-Fe-Hf

series

alloy

was

tested

by

HXD-1000B

micro-hardness tester with 136° surface angle diamond square pressure indenter. The testing load and retention time were set 300g and 20s, respectively and the average micro-hardness at 10 vertical testing points was viewed as the final result. Tensile

ACCEPTED MANUSCRIPT strength ( σ b) of W-Ni-Fe-Hf series alloy was tested by PWS-E100 electro-hydraulic servo dynamic/static universal testing machine at the loading rate of 0.1mm/min.

σ

b=F/S, where F is fracturing load and S is cross-section area of sintered samples. Surface and tensile fracture morphology of W-Ni-Fe-Hf series alloy were observed with GX-15 Olympus metalloscope and JEOL-JSM-6490LA scanning electron

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microscope as well as its accessories.

Shielding effect of W-Ni-Fe-Hf series alloy was measured by BH1326 γ-ray shielding tester with radioactive source

137

Cs (662kev), 200µmAL window NaI

scintillation probe, 72.5mm distance between γ radioactive source and probe and

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-676V high pressure. The measuring principle of shielding effect is shown in Fig.1. γ-ray is a kind of high speed photon stream. When interacting with substances, its

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most or all energies will be lost upon every impact. The bigger the atomic number of substances elements, the stronger the absorption capacity of γ-ray and the more evident the strength reduction. The narrow-beam γ-ray strength reduces significantly when it transmits through samples, indicating that samples could absorb γ-ray. The number of γ-ray backgrounds (Nb) and number of γ-ray sources (Nγ) are listed in Table 5. γ-ray strength attenuates at the law of exponent of Equation (1) when it

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transmits through substances. Calculate logarithms of both sides of Equation (4) after conversion and the relation expression of linear attenuation coefficient (Equation (5)) could be acquired. µR

ρ

··············································(1)

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N = N0e

Where N0 and N are number of γ-rays before and after transmitting through samples

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respectively; R is mass density of samples, g/mm3; µ is linear absorption coefficient of γ-rays, mm-1.

It can be known from Equation (1): µR N =e ρ N0 ················································(2)

Since R /ρ=d,

N µd =e N0 ··················································(3) Calculate logarithms of both sides,

ACCEPTED MANUSCRIPT  N  ln  ∝d  N0  ·············································(4)

In other words, the half thickness for absorption is:

d1 = 2

ln 2

µ

=

0.693

µ ······································(5)

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3. Results and discussion 3.1 X-ray diffraction analysis

Fig.2 is XRD spectra of W-Ni-Fe-Hf series alloy with different Hf contents. It is shown that The phase composition of 0#, 1#, 2#, 3#, 4# and 5# sample surfaces are

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mainly composed of W phase and γ(Ni，Fe) substrate phase after liquid phase sintering. Adding Hf affects translation of diffraction peaks of W phase and Ni-Fe

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phase significantly. The involvement of Hf changes lattice constants of W phase and Ni-Fe phase in the alloy. With the increase Hf content, lattice constant of W phase in the alloy increases firstly and then decreases, and its diffraction peak moves leftward firstly and then rightward. But the lattice constant of Ni-Fe phase increases continuously and its diffraction peak shifts leftward. When Hf content is smaller than 0.9%, the diffraction peak of W phase moves leftward quickly, while that of Ni-Fe

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phase moves leftward slowly. When Hf content is higher than 0.9%, the leftward displacement of diffraction peak of Ni-Fe phase speeds up with the increase of Hf content, whereas the diffraction peak of W crystals moves back slowly. This is because Hf dissolves in W phase firstly during the liquid phase sintering, but only few

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dissolves in the Ni-Fe substrate. However, when Hf content increases to a certain extent, excessive Hf dissolves in Ni-Fe phase. According to analysis, diffraction peak

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width of W crystals increases and W crystals shrinks after Hf is added. The backward migration of diffraction peak of W crystals reflects that Hf reaches or exceeds saturation in Ni-Fe solid solution. The diffraction peak width of W crystals is inversely proportional to Hf content, but W crystal size is proportional. 3.2 SEM morphology and EDS analysis Microstructures of W-Ni-Fe-Hf series alloy with different Hf contents were observed, as it is shown in Fig.3. The 0# sample which contains no Hf looks like an ellipsoid. Bigger round W crystals which have ambiguous boundaries are covered in the Ni-Fe substrate phase and distribute unevenly, forming a loose arrangement (Fig.3(a)). Surface morphology of the 1# sample containing 0.3% Hf is shown in

ACCEPTED MANUSCRIPT Fig.3(b). Round W crystals which have been refined significantly are wrapped in the substrate phase, presenting a tight arrangement. With the increase of Hf content, the Hf atomic reaction dissolves into the Ni-Fe substrate phase quickly, while W atoms can only diffuse into the substrate phase slowly as slid atoms. This reveals that Hf could inhibit solid solubility of W in substrate phase and growth of crystals. The EDS

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analysis found that Hf atoms account for 8.28%, but W atoms only occupy 19.36% in the Ni-Fe substrate phase of W-Ni-Fe-Hf alloy containing 0.9% Hf . Therefore, appropriate amount of Hf could refine wrapped W crystals significantly and make the crystal arrangement compact (Fig.3(c-d)). When Hf content exceeds 0.9%, the

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wrapped W crystals begin to grow, and pores between the W phase and Ni-Fe substrate phase increase (Fig.3(e)). When Hf content reaches 1.5%, the alloy surface presents different sizes of crystals and a lot of pores. This is because Hf which didn’t

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dissolved in the Ni-Fe substrate phase completely remains on the W-substrate interface, forming a new hard phase, which reduces dissolution of W crystals in the Ni-Fe substrate phase and facilitate growth of W crystals (Fig.3(f)). Table 6 is the EDS analysis of Ni-Fe substrate phase of W-Ni-Fe-Hf alloy containing 0.9% Hf. It is shown that the formation of new hard phase containing Hf

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on the surface of W-Ni-Fe-Hf alloy are formed. In the percent of 0.9Hf W-Ni-Fe-Hf alloy, 8.28% new Hf atoms were added, while the W atom content dropped to 19.36%. As the sintering temperature rising, Ni, Fe atoms combine first generation matrix phase, Hf atoms by fast dissolve into the matrix phase reaction, and W only through

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solid atoms slow diffusion into the matrix phase, so the Hf inhibits W atoms dissolved in the matrix phase, thus inhibiting the W particles grew up, have played an important

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role in refining grain, W - Ni – Fe-Hf alloy obviously improve the mechanical properties.

3.3 Tensile fracture morphology Fig.5 is a comparison of the fracture morphology of 90W - 7Ni -3Fe and 89.19

W-6.937Fe-0.9Hf alloy. It shows that 90W-7Ni-3Fe alloy without Hf mainly suffers intergranular fracture where W crystals are big and clear. And adding 0.9% Hf alloy fracture morphology is main ductile fracture and interface fracture among matrix phase W particles, and transgranular fracture of W particles is less. Adding 0.9% Hf alloy strength is significantly higher than 90W - 7Ni - 3Fe alloy. Thus it can be seen that (1) The Hf elements can be solids in the phase of the W particle and the matrix, and it can cause the solid solution each other, which makes the mechanical

ACCEPTED MANUSCRIPT properties improve significantly; (2) The Hf elements can make alloy microstructure obviously refine, the grain size of W particles in percentage of 0.9 Hf alloy is about 10 um and without content of Hf alloy the grain size of W particles is up to 30um. Thus refining the crystal structures and enhancing mechanical properties of the alloy 3.4 Mechanical properties

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Tensile strength of prepared W-Ni-Fe-Hf series alloy with different Hf contents can be measured and density of samples was tested through drainage measuring method, and micro-hardness was tested by HXD-1000B micro-hardness tester. Fig.6 shows that variation curves of density, tensile strength, elongation and micro-hardness

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of W-Ni-Fe-Hf series alloy with different Hf contents. Obviously, density, tensile strength and micro-hardness of samples increase firstly and then decreases with the increase

of

Hf

content,

but

elongation

declines

gradually.

The

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89.19W-6.937Ni-2.973Fe-0.9Hf alloy (0.9% Hf) achieves the best mechanical properties. Its sintering-state density, tensile strength and elongation are 17.07g/cm3, 925.33 MPa and 8.1%, respectively. Its microhardness is HV560.82, far higher than the alloy without Hf (HV439.911). Hf can dissolve in both W phase and Ni-Fe substrate phase. Adding appropriate amount of Hf elementary powder can reduce

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solubility of W in the Ni-Fe substrate phase and inhibits dissolution-precipitation of W atoms in the substrate phase as well as W crystal growth. Minimum quantity of Hf dissolving in the W phase and the Ni-Fe substrate phase could enhance solid dissolution, thus improving mechanical properties of the W-Ni-Fe-Hf alloys. However,

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when Hf content exceeds a certain value, the residual Hf elementary powder is very easy to form a layer of compact oxide film during the liquid phase sintering. Such

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oxide film is stable and difficult to be dissolved. Meanwhile, it is easy to form pores in the alloy, which affects densification of the alloy greatly. Surplus Hf is easy to deposit on the interface between the W phase and the Ni-e substrate phase, influencing mechanical properties of the alloy seriously. 3.5 Shielding performance A certain amount of absorbers were put between the source and detector. With the increase of absorber thickness, and transmission intensity of γ-ray was recorded. And standard lead was used as the calibration sample. Transmission intensity of γ-ray of the standard lead and W-Ni-Fe-Hf series alloy with different Hf contents was recorded in Table 7. The fitting relation curve between Ln(N/N0) and medium thickness was draw according to Equation (4), shown in Fig.6. Absorption coefficients

ACCEPTED MANUSCRIPT of W-Ni-Fe-Hf series alloy are listed in Table 8. In Fig.6, linear attenuation coefficients of γ-ray absorptivity of testing samples are far smaller than that of lead and are proportional to Hf content. On the contrary, half thickness for γ-ray absorption is inversely proportional to Hf content. The 90W-7Ni-3Fe alloy with 1.5% Hf shows the best γ-ray shielding performance. The

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γ-ray absorptivity is 0.18424 and the half thickness for γ-ray absorption reaches 3.76mm.

Half thicknesses for γ-ray absorption of W-Ni-Fe-Hf series alloy with different Hf contents were calculated from d1/2 ＝0.693/ｕ and recorded in Table 8. Half

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thicknesses for γ-ray absorption of W-Ni-Fe-Hf series alloy shielding materials with different Hf contents are all superior to that of lead materials (6.44cm), valuing 4.11 mm, 4.09 mm, 4.05 mm, 3.82 mm, 3.79mm and 3.76mm, respectively. Therefore,

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W-Ni-Fe-Hf series alloy with different Hf contents prepared from liquid phase sintering have good shielding effect to the γ radioactive source 137Cs. 4. Conclusions

W-Ni-Fe-Hf series alloys with different Hf contents are prepared by the method of liquid phase sintering. Its mechanical properties, shielding effect and

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microstructure of W-Ni-Fe-Hf alloy were analyzed. The conclusions are as follows: (1) W-Ni-Fe-Hf series alloys are mainly composed of W phase and γ(Ni，Fe) substrate phase. Hf influences translation of diffraction peaks of W phase and Ni-Fe phase significantly. The W-Ni-Fe-Hf alloy without Hf looks like an ellipsoid. With the

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increase of Hf content, the crystallization of grain on the alloy surface is obvious, as Hf could refine surface crystal greatly and make the alloy structure compact. When Hf

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content increases to 1.5%, the alloy surface presents more pores, and it is greatly poorer mechanical properties. (2) With the increase of Hf content, density, tensile strength and microhardness

of W-Ni-Fe-Hf series alloy increase firstly and then decrease, but the elongation declines gradually. The 89.19W-6.937Ni-2.973Fe-0.9Hf alloy (0.9% Hf) achieves the best mechanical properties. Its sintering-state density, tensile strength and elongation are 17.07g/cm3, 925.33 MPa and 8.1%, respectively. Its micro-hardness is HV560.82, far higher than the alloy without Hf (HV439.911). (3) Linear attenuation coefficients of γ-ray absorptivity of W-Ni-Fe-Hf series alloy are far smaller than that of lead. The half thickness for γ-ray absorption is

ACCEPTED MANUSCRIPT inversely proportional to Hf content. It indicates that prepared W-Ni-Fe-Hf series alloys with different Hf contents are significantly superior to lead in shielding γ radioactive source 137Cs. Acknowledgements The authors gratefully acknowledge the foundation by the Natural Science

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Foundation of Hunan Province with the project number 2015JJ5023; Science and Technology Major Hunan Province with the project number 2012FJ1007; Outstanding young project in hunan province department of education with the project number 5B206.

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Reference

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Li, P. L: Materials Science and

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[2] Zhang, Z. W., Zhou, J. E. Xi, S. Q. Ran, G. Engineering: A, 2004, vol. 379, pp. 148-153.

[3] HAN Zhongwu, LUAN Weiling, HAN Yanlong, ZHANG Yan, WU Guozhang. Simulation study on radiation shielding capability of tungsten nickel combination and their alloys. 2015, vol. 38, pp. 23-28

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[4] Zhu, Y. B., Wang, Y., Zhang, X. Y., Qin, G. W: International Journal of Refractory Metals and Hard Materials, 2007, vol. 25, pp. 275-279. [5] Gong, X., Fan, J. L., Ding, F., Song, M., Huang, B. Y: International Journal of Refractory Metals and Hard Materials, 2012, vol. 30, pp. 71-77.

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[6] Mondal A, Upadhyaya A, Agrawal D: Materials Science and Engineering: A, 2010, vol. 527, pp. 6870-6878.

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[7] Humail, I. S., Akhtar, F., Askari, S. J., Tufail, M., Qu, X: International Journal of Refractory Metals and hard materials, 2007, vol. 25, pp. 380-385. [8] Bahgat, M., Paek, M. K., Pak, J. J: Journal of Alloys and Compounds, 2009, vol. 472, pp. 314-318.

[9] Das, J., Kiran, U. R., Chakraborty, A., Prasad, N. E: International Journal of Refractory Metals and Hard Materials, 2009, vol. 27, pp. 577-583. [10] LIN Qing, YANG Yongx u, HE Yun, MA Yugang, ZENG Siliang: Nuclear Physics Review, 2010, vol. 27, pp. 182-186 [11] Zhang, D. Q., Liu, Z. H., Cai, Q. Z., Liu, J. H., Chua, C. K: International Journal of Refractory Metals and Hard Materials, 2014, vol. 45, pp. 15-22. [12] A Bose, RM German.Metallurgical and Materials Transactions A, 1988, vol. 19,

ACCEPTED MANUSCRIPT pp. 3100-3103 [13] Song W D, Ning J G: Mechanics and Astronomy, 2011, vol. 54, pp. 1651-1658. [14] Kiran, U. R., Panchal, A., Sankaranarayana, M., Rao, G. N., & Nandy, T. K: Materials Science and Engineering: A, 2015, vol. 640, pp. 82-90. [15] Xiulan Q, Ying H, Du Zhaofeng Y Y: Chinese Journal of Rare Metals, 2007, vol.

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5, pp. 11-17. [16] Jeon Y J, Kim S H, Kim Y D: KOREAN JOURNAL OF METALS AND

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MATERIALS, 2011, vol. 49, pp. 720-725.

ACCEPTED MANUSCRIPT Table captions: Table1 Elemental powder characteristics of W, Ni, Fe and Hf Table2 Elemental powder main impurity components of W, Ni, Fe and Hf (wt%) Table3 Number of sample and alloy composition (%) Table4 Mixed powder preparation technology and parameters

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Table5 Shielding experiment data record of background counts Nb and γ-sources counts Nγ

Table 6 EDS analysis of Ni-Fe substrate phase of W-Ni-Fe-Hf alloy containing 0.9% Hf

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Table 7 The absorbing plate γ-radiation intensity data of lead and different Hf content W-Ni-Fe series alloy

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Table 8 Comparison of the shielding capacity of lead and different Hf content

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W-Ni-Fe series alloy

ACCEPTED MANUSCRIPT Figure captions: Fig.1 Schematic diagram of W-Ni-Fe-Hf alloy shielding performance test Fig.2 XRD spectra of W-Ni-Fe-Hf series alloy with different Hf contents

（b）1#；（c）2#；（d）3#；（e）4#；（f）5#

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Fig.3 Microstructures of W-Ni-Fe-Hf series alloy with different Hf contents:（a）0#；

Fig.4 The tensile fracture surface morphology of W-Ni-Fe alloy containing 0.9% Hf and no Hf

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Fig. 5 The curve of mechanical properties on different percent of Hf W-Ni-Fe-Hf series alloy sample: (a) Strength, (b) Density, (c) Hardness, (d) Elongation

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Fig. 6 The shielding capacity of W-Ni-Fe-Hf samples with different Hf contents: (a)

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Lead, (b) 1#, (c) 2#, (d) 3#, (e) 4#, (f) 5#

ACCEPTED MANUSCRIPT Table1

-3

Density (g.cm ) preparation methods

Ni

Fe

Hf

3.0 3.6 Reduction method ≥99.8

2.2 0.6

75 2.6 Carbonyl method ≥99.5

3 Atomization method ≥99.5

Carbonyl method ≥99.5

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Purity (%)

W

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powder characteristics Particle size (um)

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impurities

percentage composition

W

C O

0.01 0.004

Ni

C O

0.2 0.15

Fe

C S Si Mn P

0.02 0.01 0.05 0.04 0.01

Hf

Zr N C O H Fe Mg

SC 0.12 0.06 0.05 0.03 0.001 0.01 0.01

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Elemental powder

ACCEPTED MANUSCRIPT Table3

alloy composition（%） W Ni Fe Hf 90 89.73 89.46 89.19

7 6.979 6.958 6.937

3 2.991 2.982 2.973

0 0.3 0.6 0.9

4#

88.92

6.916

2.964

1.2

5#

88.65

6.895

2.955

1.5

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0# 1# 2# 3#

preparation of sample

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Sample No

ACCEPTED MANUSCRIPT Table4 parameters

Mixing equipment Speed (r/min) Blending method Wet grinding medium ratio of grinding media to material Grinding time (h) Drying temperature (K) Drying time (h)

QM High speed vibration ball mill machine 100 Wet grinding C2H5OH 2 1

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1 279 4

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preparation technology

ACCEPTED MANUSCRIPT Table5

N1

N2

N3

N4

N5

NV

N0= Nγ- Nb

Nb Nγ

2889 27193

2860 27503

2839 27413

2910 27407

2893 27582

2878.2 27419.6

24541.4

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Sample No

ACCEPTED MANUSCRIPT Table 6

Ni

Fe

Hf

A B C D

97.41 95.66 77.52 19.88

1.85 2.38 13.77 48.33

0.58 1.22 4.69 23.76

0.16 0.74 4.02 8.14

E

19.36

48.49

23.87

8.28

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W

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alloy composition（%）

Analysis of the position

ACCEPTED MANUSCRIPT Table 7

2#

3#

N4

N5

NV

N= Nv- Nb

Ln（N/N0）

5

16569

16411

16571

16437

16491

16495.8

13617.6

-0.588998

5.2

16384

16396

16378

16401

16414

16394.6

13516.4

-0.596457

10

10775

10828

10881

10869

10910

10852.6

7974.4

-1.124125

10.2

10680

10754

10719

10779

10739

10734.2

7856

-1.139083

2

22400

22677

22537

22366

22408

22477.6

19599.4

-0.224862

4

17411

17453

17340

17123

17528

17371

14492.8

-0.526709

6

13623

13631

13577

13585

13623

13607.8

10729.6

-0.827355

8

10564

10588

10606

10614

10542

10582.8

7704.6

-1.158543

2

22016

21997

22218

21990

21905

22025.2

19147

-0.248215

4

16477

16519

16504

16446

16721

6

12473

12524

12761

12648

12680

8

9782

9603

9851

9734

9874

10

7729

7818

7927

7676

8009

2

22098

21618

21976

21766

4

16555

16185

16417

6

12650

12662

8

9479

10

13655.2

-0.586241

12617.2

9739

-0.924223

9768.8

6890.6

-1.270203

7831.8

4953.6

-1.600246

21826

21856.8

18978.6

-0.257049

16216

16496

16373.8

13495.6

-0.597997

12755

12470

12435

12594.4

9716.2

-0.926566

9494

9409

9505

9418

9461

6582.8

-1.315901

7679

7768

7877

7626

7959

7781.8

4903.6

-1.610391

2

21369

21457

21636

21571

21477

21502

18623.8

-0.275921

4

16053

16271

16061

16044

16287

16143.2

13265

-0.615232

6

12400

12203

12130

12437

12338

12301.6

9423.4

-0.957165

8

9178

9191

9040

9216

9114

9147.8

6269.6

-1.364648

10

7266

7214

7455

7255

7233

7284.6

4406.4

-1.717303

2

21585

21423

21804

21317

21380

21501.8

18623.6

-0.275931

6

16065

15976

16105

16168

16123

16087.4

13209.2

-0.619447

12167

12417

12183

12359

12145

12254.2

9376

-0.962208

9047

9239

9300

8908

8981

9095

6216.8

-1.373106

AC C

8

5#

SC 16533.4

4 4#

RI PT

N3

M AN U

1#

N2

TE D

0#

N1

EP

lead

Thickness

10

7196

7248

7263

7293

7157

7231.4

4353.2

-1.729450

2

21080

21361

21580

21445

21467

21386.6

18508.4

-0.282136

4

15688

15979

16071

15954

15924

15923.2

13045

-0.631956

6

11949

12171

11999

12148

12075

12068.4

9190.2

-0.982223

8

8884

8985

9225

8934

8945

8994.6

6116.4

-1.389387

10

7233

7191

7132

7142

7106

7160.8

4282.6

-1.745801

ACCEPTED MANUSCRIPT Table 8

Half absorptive thickness（mm） 6.44 4.11 4.09 4.05 3.82 3.79 3.76

AC C

EP

TE D

M AN U

SC

Lead 0# 1# 2# 3# 4# 5#

Absorption coefficient (µ) 0.10769 0.16875 0.16940 0.17123 0.18161 0.18303 0.18424

RI PT

Density （g/cm3） 11.34 16.99 17.04 17.06 17.07 17.05 17.01

sample

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

ACCEPTED MANUSCRIPT

Highlight (1) Good shielding Effect of W-Ni-Fe Alloy is prepared through liquid phase sintering. (2) W-Ni-Fe-Hf series alloys are mainly composed of W phase and γ(Ni，Fe) substrate phase.

RI PT

(3) When Hf content increases to 1.5%, the mechanical properties of alloy are greatly poorer.

(4) The mechanical properties of 89.19W-6.937Ni-2.973Fe-0.9Hf alloy (0.9% Hf) is the best..

SC

(5) Prepared W-Ni-Fe-Hf series alloys are significantly superior to lead in shielding γ

AC C

EP

TE D

M AN U

ray.