- Email: [email protected]
Microstructural and mechanical characterization of copper, nickel, and Cu-based alloys obtained by mechanical alloying and hot pressing
Accepted Manuscript Microstructural and Mechanical Characterization of Copper, Nickel, and CuBased Alloys Obtained by Mechanical Alloying and Hot Pressing C. Martínez, F. Briones, P. Rojas, C. Aguilar, D. Guzman, S. Ordoñez PII: DOI: Reference:
S0167-577X(17)31282-X http://dx.doi.org/10.1016/j.matlet.2017.08.082 MLBLUE 23059
To appear in:
Materials Letters
Received Date: Revised Date: Accepted Date:
1 June 2017 8 August 2017 21 August 2017
Please cite this article as: C. Martínez, F. Briones, P. Rojas, C. Aguilar, D. Guzman, S. Ordoñez, Microstructural and Mechanical Characterization of Copper, Nickel, and Cu-Based Alloys Obtained by Mechanical Alloying and Hot Pressing, Materials Letters (2017), doi: http://dx.doi.org/10.1016/j.matlet.2017.08.082
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.
Microstructural and Mechanical Characterization of Copper, Nickel, and Cu-Based Alloys Obtained by Mechanical Alloying and Hot Pressing
C. Martínez1*, F.Briones2, P. Rojas3, C. Aguilar4, D. Guzman5, S. Ordoñez6.
1
Laboratorio de Corrosión, Instituto de Química, Pontificia Universidad Católica de Valparaíso, 3100000, Valparaíso, Chile
2
Escuela de Ingeniería Mecánica, Pontificia Universidad Católica de Valparaíso, 2430120, Quilpué, Chile.
3
Escuela de Diseño, Universidad Adolfo Ibáñez, 7941169, Santiago, Chile
4
Departamento de Ingeniería Metalúrgica y Materiales, Universidad Técnica Federico Santa María, 2390123, Valparaíso, Chile
5
Departamento de Metalurgia, Universidad de Atacama, 1531772, Copiapó, Chile
6
Departamento de Metalurgia, Universidad de Santiago de Chile, 9170022, Santiago, Chile
*Corresponding author: [email protected]
ABSTRACT Mechanical alloying and uniaxial compaction were used to obtain configurations of: elemental powders of Cu and Ni; binary alloys (Cu-Ni and Cu-Zr); and a ternary alloy (CuNi-Zr) under the same mechanical milling and hot pressing conditions. Microstructure and mechanical properties of these were investigated. According to XRD results, hot pressing process increases crystallite size and decreases microstrain in the compact samples, due to
1
the release of crystalline defects without crystallization of amorphous alloys. The milled powder samples have a higher hardness than the unmilled samples, since crystal defects are incorporated into microstructural refinement during milling. The ternary alloy Cu-40Ni10Zr had the highest hardness of all systems studied, reaching 689 HV0.5. Compression tests at 5% strain determined that Zr-containing samples (amorphous phase) become more fragile after processing, and have the lowest values of compressive strength. In contrast, Ni samples and Cu-Ni binary alloys are more resistant to compression.
Keywords: Cu-Based Alloys; Mechanical Alloying; Mechanical properties.
INTRODUCTION Nanostructured materials are of great interest, due to improvements in their properties, especially chemical and mechanical. These include high corrosion resistance [1], fracture strength [2], and wear resistance [3], as compared to micro- or macrostructured counterparts. The differences in the properties of these materials are produced by the greater number of interfaces that can act as barriers against slip dislocations, which are able to control and reduce the propagation direction of cracks, which increases hardness and toughness. Metallic glasses have been known since 1960 [4], when Clement and Duwez studied amorphous Au75Si25 by rapid quenching synthesis. Since 1988, a number of alloys with a high glass-forming ability and able to be fabricated as bulk metallic glasses (BMGs) [5]. BMG materials have become one of the most popular topics in the field of materials
2
science, due to their properties of excellent wear resistance, high corrosion resistance, high hardness, low Young modulus, and high resistance to fatigue [6-9]. High energy milling alloying processes can produce metals, intermetallic compounds [10, 11], ceramic, and composite materials with grain size on the nanometer scale [12]. These processes produce significant microstructural and morphological changes due to significant deformations introduced into the powders. These deformations, in turn, lead to increased crystal defects, such as dislocations, voids, stacking faults, twins formation, a larger amount of grain boundaries, and microstructural refinement at the nanometer scale [13]. Moreover, mechanical alloying (MA) of metallic glasses is a highlystudied manufacturing method provides wide ranges of composition for the formation of metallic glasses, in contrast to conventional processes [13, 14]. Consolidation processes, like hot pressing, provide an advantage in the production of complex parts without limitation in shape and dimensions [15]. Cu-based alloys obtained by mechanical alloying have been investigated [16-17], as well as the effect of adding components to the MA process (Cu, Ni, Cu-Ni, and Cu-Zr) [1820]. For this reason, this study will look at the different components of the Cu-Ni-Zr system under the same milling and hot pressing conditions to evaluate microstructural and mechanical properties. EXPERIMENT Mechanical milling and mechanical alloying were performed with pure powders: Cu (99.7 at. %, < 63 µm mesh, Merck), Ni (99 at. %, <230 mesh, Merck), and Zr (99.8 at. %, <50 mesh, Noah Technologies). The milling operations were carried out on powder
3
compositions of 100Cu, 100Ni, Cu-50Ni, Cu-50Zr, Cu-10Ni-40Zr, Cu-40Ni-10Zr (wt. %). High-energy milling was performed in a SPEX 8000D mill using stainless steel containers and balls. The BPR in all cases was 10:1 and included stearic acid (1 wt. %) as a control agent, with a milling time of 5 hours, previous studies [18-20]. Uni-axial hot pressing was carried out in a hydraulic press under uniaxial pressure of 900 MPa at 300°C. The samples were characterized by X-ray diffraction to identify and evaluate the phase purity. The characterization was performed with a Shimadzu XDR 6000 diffractometer in Bragg-Brentano reflection geometry with Cu Kα radiation. The crystallite size and microstrain were determined by a Modified Williamson-Hall model [21]. The iron content was measured using a GBS 905 atomic absorption spectrometer. The microstructures were analyzed by scanning electron microscopy on HITACHI SU 3500 equipment. The mechanical properties were studied by compression tests with Tinius Olsen super-L model certified universal machine and hardness in Vickers scale (HV0.5) on polished surfaces at RT.
RESULTS AND DISCUSSION
Figure 1 shows the microstructural changes produced by hot pressing were studied by X-ray diffraction. As shown in the figure, the same milling and hot pressing conditions affected these samples differently. Note that in the case of compacted nickel, a minor second phase (hexagonal Ni) is observed (fig. 1a). This is noteworthy, since hexagonal nickel is generally obtained through chemical reduction [22, 23].
4
Figure 1. XRD spectra of a) pure element: Cu and Ni, b) binary alloys: Cu-50Ni and Cu50Zr and c) ternary alloys: Cu-10Ni-40Zr and Cu-40Ni-10Zr, after 5 h milling time and hot pressing (x Zr, * Cu-Ni solid solution). CS: Crystallite Size; MS: Microstrain
Defects incorporated during mechanical milling were quantified by means of WH calculations, in accordance with other studies making use of this methodology [20, 24]. One such defect, microstrain, is produced by the presence of dislocations and solute atoms in a solid solution. Specifically, solute atoms enter the solution and move to neighboring
5
atoms of the crystal lattice away from equilibrium position, due to different atomic radii. This microstrain causes an increase in the local energy, and hence the internal energy, of the system; in effect, the solute atoms that enter the solid solution decrease the local energy, which is required for a fault occurrence. The peaks of the hot-pressed samples are narrower (Fig. 1) than those of the as-milled powders, which is due to strain relaxation and grain growth during hot pressing. In the Cu-50Zr (fig. 1b) and Cu-10Ni-40Zr (fig. 1c) alloys, no intermetallic phases were formed. The greater the amount of Zr in the sample, the lower the crystallinity observed, i.e. Zr promotes amorphization of the system. Crystallization is a predominating problem that has to be overcome during consolidation of amorphous powder [25]. This inconvenient is not observed by the low temperature of consolidation of the powders.
Figure 2. SEM images consolidated samples: a) pure Cu and b) Cu-10Ni-40Zr
After hot pressing, the presence of pores in the compactions was observed through electron microscopy (Figure 2). As shown in Figure 2a, the sample with lowest porosity was pure copper. In compacted samples of both the pure elements (Cu and Ni), it is observed that Ni 6
has a higher hardness than Cu; this may be attributed to the fact that Ni has a greater capacity for incorporation of crystalline defects [20] and powder morphology difference; Cu powder is flakes and Ni irregular agglomerates. This morphology is attributed to the continuous welding and fracturing of the powder particles during the MA [13]. In addition, one should consider that Ni has higher Fe (0,3 wt.%) contamination from the milling container, which promotes hardening by forming a solid solution [26].With respect to binary and ternary alloys, the incorporation of alloying elements produces a greater distortion in the crystal lattice material and hardness is increased, which decreases the consolidation ability of the powders for which more porous compactions are obtained (see Table I). The amorphous phase decreased packing efficiency is associated with maximization of entropy and thus free energy.
Table I. Density of compacted samples (% DT), hardness (Vickers) and compressive strength at 5% strain for each sample. Compression Sample
Density
Vickers Hardness
strength at 5%
(% DT)
(HV0,5)
strain (Kgf/mm2)
Cu_5 h HP
93
203
23
Ni_5 h HP
76
617
49
Cu-50Ni HP
78
526
33
Cu-50Zr HP
74
475
12
Cu-10Ni-40Zr_5 h HP
72
678
9
Cu-40Ni-10Zr_5 h HP
73
689
10
7
Table I shows hardness and compression strength at 5 % strain of samples all. Pure elements, Nickel achieves a high hardness as compared with copper which influences also in alloys with higher amount of nickel present. Cu-40Ni-10Zr presents the maximum hardness of the series of samples studied. On the other hand, in the compressive strength determined at 5% strain of pure elements, the Cu-Ni alloy presents intermediate values between pure Cu and Ni, but when Zr is present in the system, the material becomes brittle and the resistance to compression is noticeably reduced. First, it is attributed to that during compaction, particles low cohesion producing early fracture of the material results in low compressive strength. Second, it is known that bulk metallic glasses show a macroscopically quite brittle deformation behavior at room temperature and perform at near theoretical strength before failure due to the dislocation-based absence of plasticity [26].
CONCLUSIONS
Hot pressing parameters are not the usual and achieve a copper density of 93% and do not produce crystallization of the amorphous material. The consolidation of the powders did not noticeably affect the samples, except in the case of pure Ni, with the emergence of hexagonal Ni. It was shown that Ni and Zr also affect the density of the material. The ternary alloy had the highest hardness of all systems studied, reaching 689 HV0.5. Compression tests at 5% strain determined that Zr-containing samples become more fragile after processing, with the lowest values of compressive strength. In contrast, Ni and Cu-Ni binary alloy samples are more compression strength.
8
ACKNOWLEDGMENTS This project was supported by the FONDECYT program, project number 3140207 and 1130475.
REFERENCES 1. W.H Peter, W.H. Buchanan, R.A. Liu, C.T. et al., Intermetallics. 10, 1157 (2002). 2.
C. Suryanarayana, Int. Mater. Rev. 40, 41 (1995).
3.
D.H. Jeong, F. Gonzalez, G. Palumbo, K.T. Aust, U. Erb, Scripta Mater. 44, 493 (2001).
4.
W. Clement, R.H. Willens, P. Duwez, Nature 187, 869 (1960).
5.
A. Takeuchi and A. Inoue, Materials Transactions. 46, 2817 (2005)
6.
A. Kawashima, K. Ohmura, Y. Yokoyama, A. Inoue, Corros. Sci. 53, 2778 (2011).
7.
W.H. Wang, C. Dong, C.H. Shek, Mater. Sci. Eng. A 44, 45 (2004).
8.
C. A. Schuh, T. C. Hufnagel, U. Ramamurty, Acta Mater. 55, 4067 (2007).
9.
A. Inoue, X. M Wang, W. Zhang, Rev. Adv. Mater. Sci. 18, 1 (2008).
10. C. Martínez, S. Ordoñez, D. Guzmán, D. Serafini, I. Iturriza, O. Bustos, J. Alloy Compd. 580, 241(2013). 11. C. Martínez, S. Ordoñez, D. Serafini, D. Guzmán, P.A. Rojas, J. Alloy Compd. 590, 469 (2014). 12. D.L. Zhang, Prog. Mater. Sci. 49, 537 (2004). 13. C. Suryanarayana, Prog. Mater. Sci. 46, 1 (2001). 14. J. Eckert, Mater. Sci. Eng. A. 226, 364 (1997).
9
15. H.J. Kim, J.K. Lee, S.Y. Shin, et al., Intermetallics 12, 1109 (2004). 16. P.A. Rojas, A. Peñaloza, et al., J. Alloy Compd. 425, 334 (2006). 17. C. Aguilar, D. Guzmán, P.A. Rojas, et al, Mater. Chem. Phys. 128, 539 (2011). 18. C. Martínez, P. Rojas, C. Aguilar, D. Guzmán, E. Zelaya, Rev. Materia 20, 621 (2015). 19. P. Rojas, C. Martínez, F. Viancos, C. Aguilar, D. Guzmán, E. Zelaya, Rev. Materia 20, 705 (2015). 20. T. Ungár and A. Borbély, Appl. Phys. Lett. 69, 3173 (1996). 21. G. Carturan, Mater. Lett. 7, 47 (1988). 22. A. Lahiri, R. Das, R. G. Reddy, J. Power Sources 195, 1688 (2010). 23. A. Nazari, M. Zakeri, Ceram. Inter. 39, 1587 (2013). 24. P.A. Rojas, C. Martínez, C. Aguilar, et al., Ing. Investig. 36, 102 (2016) 25. M.H. Enayati, F.A. Mohamed, Int. Mater. Rev. 59, 394 (2014). 26. J. Eckert, J. Das, K.B. Kim, F. Baier, et al., Intermetallics 14, 876 (2006).
10
Highlights •
Microstructure and mechanical properties of Cu-Based Alloys were investigated.
•
Microstructure changes during hot uniaxial pressing were determined.
•
The feasibility to obtain Cu-Ni-Zr amorphous by has been established.
•
The hardness and compressive strength for all samples were obtained.
11
S0167-577X(17)31282-X http://dx.doi.org/10.1016/j.matlet.2017.08.082 MLBLUE 23059
To appear in:
Materials Letters
Received Date: Revised Date: Accepted Date:
1 June 2017 8 August 2017 21 August 2017
Please cite this article as: C. Martínez, F. Briones, P. Rojas, C. Aguilar, D. Guzman, S. Ordoñez, Microstructural and Mechanical Characterization of Copper, Nickel, and Cu-Based Alloys Obtained by Mechanical Alloying and Hot Pressing, Materials Letters (2017), doi: http://dx.doi.org/10.1016/j.matlet.2017.08.082
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.
Microstructural and Mechanical Characterization of Copper, Nickel, and Cu-Based Alloys Obtained by Mechanical Alloying and Hot Pressing
C. Martínez1*, F.Briones2, P. Rojas3, C. Aguilar4, D. Guzman5, S. Ordoñez6.
1
Laboratorio de Corrosión, Instituto de Química, Pontificia Universidad Católica de Valparaíso, 3100000, Valparaíso, Chile
2
Escuela de Ingeniería Mecánica, Pontificia Universidad Católica de Valparaíso, 2430120, Quilpué, Chile.
3
Escuela de Diseño, Universidad Adolfo Ibáñez, 7941169, Santiago, Chile
4
Departamento de Ingeniería Metalúrgica y Materiales, Universidad Técnica Federico Santa María, 2390123, Valparaíso, Chile
5
Departamento de Metalurgia, Universidad de Atacama, 1531772, Copiapó, Chile
6
Departamento de Metalurgia, Universidad de Santiago de Chile, 9170022, Santiago, Chile
*Corresponding author: [email protected]
ABSTRACT Mechanical alloying and uniaxial compaction were used to obtain configurations of: elemental powders of Cu and Ni; binary alloys (Cu-Ni and Cu-Zr); and a ternary alloy (CuNi-Zr) under the same mechanical milling and hot pressing conditions. Microstructure and mechanical properties of these were investigated. According to XRD results, hot pressing process increases crystallite size and decreases microstrain in the compact samples, due to
1
the release of crystalline defects without crystallization of amorphous alloys. The milled powder samples have a higher hardness than the unmilled samples, since crystal defects are incorporated into microstructural refinement during milling. The ternary alloy Cu-40Ni10Zr had the highest hardness of all systems studied, reaching 689 HV0.5. Compression tests at 5% strain determined that Zr-containing samples (amorphous phase) become more fragile after processing, and have the lowest values of compressive strength. In contrast, Ni samples and Cu-Ni binary alloys are more resistant to compression.
Keywords: Cu-Based Alloys; Mechanical Alloying; Mechanical properties.
INTRODUCTION Nanostructured materials are of great interest, due to improvements in their properties, especially chemical and mechanical. These include high corrosion resistance [1], fracture strength [2], and wear resistance [3], as compared to micro- or macrostructured counterparts. The differences in the properties of these materials are produced by the greater number of interfaces that can act as barriers against slip dislocations, which are able to control and reduce the propagation direction of cracks, which increases hardness and toughness. Metallic glasses have been known since 1960 [4], when Clement and Duwez studied amorphous Au75Si25 by rapid quenching synthesis. Since 1988, a number of alloys with a high glass-forming ability and able to be fabricated as bulk metallic glasses (BMGs) [5]. BMG materials have become one of the most popular topics in the field of materials
2
science, due to their properties of excellent wear resistance, high corrosion resistance, high hardness, low Young modulus, and high resistance to fatigue [6-9]. High energy milling alloying processes can produce metals, intermetallic compounds [10, 11], ceramic, and composite materials with grain size on the nanometer scale [12]. These processes produce significant microstructural and morphological changes due to significant deformations introduced into the powders. These deformations, in turn, lead to increased crystal defects, such as dislocations, voids, stacking faults, twins formation, a larger amount of grain boundaries, and microstructural refinement at the nanometer scale [13]. Moreover, mechanical alloying (MA) of metallic glasses is a highlystudied manufacturing method provides wide ranges of composition for the formation of metallic glasses, in contrast to conventional processes [13, 14]. Consolidation processes, like hot pressing, provide an advantage in the production of complex parts without limitation in shape and dimensions [15]. Cu-based alloys obtained by mechanical alloying have been investigated [16-17], as well as the effect of adding components to the MA process (Cu, Ni, Cu-Ni, and Cu-Zr) [1820]. For this reason, this study will look at the different components of the Cu-Ni-Zr system under the same milling and hot pressing conditions to evaluate microstructural and mechanical properties. EXPERIMENT Mechanical milling and mechanical alloying were performed with pure powders: Cu (99.7 at. %, < 63 µm mesh, Merck), Ni (99 at. %, <230 mesh, Merck), and Zr (99.8 at. %, <50 mesh, Noah Technologies). The milling operations were carried out on powder
3
compositions of 100Cu, 100Ni, Cu-50Ni, Cu-50Zr, Cu-10Ni-40Zr, Cu-40Ni-10Zr (wt. %). High-energy milling was performed in a SPEX 8000D mill using stainless steel containers and balls. The BPR in all cases was 10:1 and included stearic acid (1 wt. %) as a control agent, with a milling time of 5 hours, previous studies [18-20]. Uni-axial hot pressing was carried out in a hydraulic press under uniaxial pressure of 900 MPa at 300°C. The samples were characterized by X-ray diffraction to identify and evaluate the phase purity. The characterization was performed with a Shimadzu XDR 6000 diffractometer in Bragg-Brentano reflection geometry with Cu Kα radiation. The crystallite size and microstrain were determined by a Modified Williamson-Hall model [21]. The iron content was measured using a GBS 905 atomic absorption spectrometer. The microstructures were analyzed by scanning electron microscopy on HITACHI SU 3500 equipment. The mechanical properties were studied by compression tests with Tinius Olsen super-L model certified universal machine and hardness in Vickers scale (HV0.5) on polished surfaces at RT.
RESULTS AND DISCUSSION
Figure 1 shows the microstructural changes produced by hot pressing were studied by X-ray diffraction. As shown in the figure, the same milling and hot pressing conditions affected these samples differently. Note that in the case of compacted nickel, a minor second phase (hexagonal Ni) is observed (fig. 1a). This is noteworthy, since hexagonal nickel is generally obtained through chemical reduction [22, 23].
4
Figure 1. XRD spectra of a) pure element: Cu and Ni, b) binary alloys: Cu-50Ni and Cu50Zr and c) ternary alloys: Cu-10Ni-40Zr and Cu-40Ni-10Zr, after 5 h milling time and hot pressing (x Zr, * Cu-Ni solid solution). CS: Crystallite Size; MS: Microstrain
Defects incorporated during mechanical milling were quantified by means of WH calculations, in accordance with other studies making use of this methodology [20, 24]. One such defect, microstrain, is produced by the presence of dislocations and solute atoms in a solid solution. Specifically, solute atoms enter the solution and move to neighboring
5
atoms of the crystal lattice away from equilibrium position, due to different atomic radii. This microstrain causes an increase in the local energy, and hence the internal energy, of the system; in effect, the solute atoms that enter the solid solution decrease the local energy, which is required for a fault occurrence. The peaks of the hot-pressed samples are narrower (Fig. 1) than those of the as-milled powders, which is due to strain relaxation and grain growth during hot pressing. In the Cu-50Zr (fig. 1b) and Cu-10Ni-40Zr (fig. 1c) alloys, no intermetallic phases were formed. The greater the amount of Zr in the sample, the lower the crystallinity observed, i.e. Zr promotes amorphization of the system. Crystallization is a predominating problem that has to be overcome during consolidation of amorphous powder [25]. This inconvenient is not observed by the low temperature of consolidation of the powders.
Figure 2. SEM images consolidated samples: a) pure Cu and b) Cu-10Ni-40Zr
After hot pressing, the presence of pores in the compactions was observed through electron microscopy (Figure 2). As shown in Figure 2a, the sample with lowest porosity was pure copper. In compacted samples of both the pure elements (Cu and Ni), it is observed that Ni 6
has a higher hardness than Cu; this may be attributed to the fact that Ni has a greater capacity for incorporation of crystalline defects [20] and powder morphology difference; Cu powder is flakes and Ni irregular agglomerates. This morphology is attributed to the continuous welding and fracturing of the powder particles during the MA [13]. In addition, one should consider that Ni has higher Fe (0,3 wt.%) contamination from the milling container, which promotes hardening by forming a solid solution [26].With respect to binary and ternary alloys, the incorporation of alloying elements produces a greater distortion in the crystal lattice material and hardness is increased, which decreases the consolidation ability of the powders for which more porous compactions are obtained (see Table I). The amorphous phase decreased packing efficiency is associated with maximization of entropy and thus free energy.
Table I. Density of compacted samples (% DT), hardness (Vickers) and compressive strength at 5% strain for each sample. Compression Sample
Density
Vickers Hardness
strength at 5%
(% DT)
(HV0,5)
strain (Kgf/mm2)
Cu_5 h HP
93
203
23
Ni_5 h HP
76
617
49
Cu-50Ni HP
78
526
33
Cu-50Zr HP
74
475
12
Cu-10Ni-40Zr_5 h HP
72
678
9
Cu-40Ni-10Zr_5 h HP
73
689
10
7
Table I shows hardness and compression strength at 5 % strain of samples all. Pure elements, Nickel achieves a high hardness as compared with copper which influences also in alloys with higher amount of nickel present. Cu-40Ni-10Zr presents the maximum hardness of the series of samples studied. On the other hand, in the compressive strength determined at 5% strain of pure elements, the Cu-Ni alloy presents intermediate values between pure Cu and Ni, but when Zr is present in the system, the material becomes brittle and the resistance to compression is noticeably reduced. First, it is attributed to that during compaction, particles low cohesion producing early fracture of the material results in low compressive strength. Second, it is known that bulk metallic glasses show a macroscopically quite brittle deformation behavior at room temperature and perform at near theoretical strength before failure due to the dislocation-based absence of plasticity [26].
CONCLUSIONS
Hot pressing parameters are not the usual and achieve a copper density of 93% and do not produce crystallization of the amorphous material. The consolidation of the powders did not noticeably affect the samples, except in the case of pure Ni, with the emergence of hexagonal Ni. It was shown that Ni and Zr also affect the density of the material. The ternary alloy had the highest hardness of all systems studied, reaching 689 HV0.5. Compression tests at 5% strain determined that Zr-containing samples become more fragile after processing, with the lowest values of compressive strength. In contrast, Ni and Cu-Ni binary alloy samples are more compression strength.
8
ACKNOWLEDGMENTS This project was supported by the FONDECYT program, project number 3140207 and 1130475.
REFERENCES 1. W.H Peter, W.H. Buchanan, R.A. Liu, C.T. et al., Intermetallics. 10, 1157 (2002). 2.
C. Suryanarayana, Int. Mater. Rev. 40, 41 (1995).
3.
D.H. Jeong, F. Gonzalez, G. Palumbo, K.T. Aust, U. Erb, Scripta Mater. 44, 493 (2001).
4.
W. Clement, R.H. Willens, P. Duwez, Nature 187, 869 (1960).
5.
A. Takeuchi and A. Inoue, Materials Transactions. 46, 2817 (2005)
6.
A. Kawashima, K. Ohmura, Y. Yokoyama, A. Inoue, Corros. Sci. 53, 2778 (2011).
7.
W.H. Wang, C. Dong, C.H. Shek, Mater. Sci. Eng. A 44, 45 (2004).
8.
C. A. Schuh, T. C. Hufnagel, U. Ramamurty, Acta Mater. 55, 4067 (2007).
9.
A. Inoue, X. M Wang, W. Zhang, Rev. Adv. Mater. Sci. 18, 1 (2008).
10. C. Martínez, S. Ordoñez, D. Guzmán, D. Serafini, I. Iturriza, O. Bustos, J. Alloy Compd. 580, 241(2013). 11. C. Martínez, S. Ordoñez, D. Serafini, D. Guzmán, P.A. Rojas, J. Alloy Compd. 590, 469 (2014). 12. D.L. Zhang, Prog. Mater. Sci. 49, 537 (2004). 13. C. Suryanarayana, Prog. Mater. Sci. 46, 1 (2001). 14. J. Eckert, Mater. Sci. Eng. A. 226, 364 (1997).
9
15. H.J. Kim, J.K. Lee, S.Y. Shin, et al., Intermetallics 12, 1109 (2004). 16. P.A. Rojas, A. Peñaloza, et al., J. Alloy Compd. 425, 334 (2006). 17. C. Aguilar, D. Guzmán, P.A. Rojas, et al, Mater. Chem. Phys. 128, 539 (2011). 18. C. Martínez, P. Rojas, C. Aguilar, D. Guzmán, E. Zelaya, Rev. Materia 20, 621 (2015). 19. P. Rojas, C. Martínez, F. Viancos, C. Aguilar, D. Guzmán, E. Zelaya, Rev. Materia 20, 705 (2015). 20. T. Ungár and A. Borbély, Appl. Phys. Lett. 69, 3173 (1996). 21. G. Carturan, Mater. Lett. 7, 47 (1988). 22. A. Lahiri, R. Das, R. G. Reddy, J. Power Sources 195, 1688 (2010). 23. A. Nazari, M. Zakeri, Ceram. Inter. 39, 1587 (2013). 24. P.A. Rojas, C. Martínez, C. Aguilar, et al., Ing. Investig. 36, 102 (2016) 25. M.H. Enayati, F.A. Mohamed, Int. Mater. Rev. 59, 394 (2014). 26. J. Eckert, J. Das, K.B. Kim, F. Baier, et al., Intermetallics 14, 876 (2006).
10
Highlights •
Microstructure and mechanical properties of Cu-Based Alloys were investigated.
•
Microstructure changes during hot uniaxial pressing were determined.
•
The feasibility to obtain Cu-Ni-Zr amorphous by has been established.
•
The hardness and compressive strength for all samples were obtained.
11