Hostname: page-component-848d4c4894-x24gv Total loading time: 0 Render date: 2024-04-30T20:39:00.028Z Has data issue: false hasContentIssue false
  • English
  • Français

Hardening by Crystallization During Superplastic Flow in a Powder-metallurgy-processed Zr65Al10Ni10Cu15 Glass Metallic Alloy

Published online by Cambridge University Press:  01 June 2005

H.G. Jeong  and
W.J. Kim
H.G. Jeong
Affiliation:
Digital Production Processing Team, Korea Institute of Industrial Technology, Incheon Metropolitan City 406-130, Korea
W.J. Kim*
Affiliation:
Department of Materials Science and Engineering, Hong-Ik University, Seoul 121-791, Korea
*
a) Address all correspondence to this author. e-mail: kimwj@wow.hongik.ac.kr
Get access

Abstract

The superplastic behavior of the Zr65Al10Ni10Cu15 glass metallic alloy produced by the powder metallurgy method was examined in the supercooled liquid region. A tensile elongation as large as 750% was obtained at 6.3 × 10−3 s−1 at 697 K. Large strain hardening took place during the course of deformation and systematic trend was observed in the hardening behavior. Plots of stress versus strain and strain rate versus stress at 697 K showed that Newtonian viscous flow governed the plastic flow until the onset of strain hardening. Microstructure and differential scanning calorimetry analyses as well as flow stress versus testing time curves provided consistent evidence that the strain hardening was induced by crystallization. Crystallization was enhanced in the gauge region (deformed region) as compared to the grip region (undeformed region). Crystallization is expected to decrease tensile ductility by decreasing the strain-rate-sensitivity value and increasing the degree of brittleness. Hardening by crystallization, however, can contribute to neck stability if crystallization is enhanced in the neck region. The strain hardening and plastic stability parameters were measured as a function of strain for different strain rates at 696 K. The strain hardening parameter remained highly positive until failure. Because of this, the neck stability parameter (I) could be I < 0 in the entire hardening region. The contribution of hardening by crystallization to neck stability was found to be much more significant than that by grain growth in the superplastic metallic alloys. Reducing the specimen heating-and-holding time was suggested to promote superplasticity deformation without delaying initiation of crystallization. The largest tensile strain in the hardening region where crystallization may be obtained at the strain rates and temperatures where crystallization rate is controlled to be the lowest while maintaining I ≤ 0 throughout deformation.

Keywords

Metallic glassMicrostructureSuperplasticity
Type
Articles
Information
Journal of Materials Research , Volume 20 , Issue 6 , June 2005 , pp. 1447 - 1455
Copyright
Copyright © Materials Research Society 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Inoue, A., Kimura, H.M., Sasamori, K. and Masumoto, T.: Ultrahigh strength of rapidly solidified Al96− x Cr3Ce1Cox (x - 1, 1.5 and 2%) alloys containing an icosahedral phase as a main component. Mater. Trans., JIM 35, 85 (1994).CrossRefGoogle Scholar
2Hays, C.C., Kim, C.P. and Johnson, W.L.: Improved mechanical behavior of bulk metallic glasses containing in situ formed ductile phase dendrite dispersions. Phys. Rev. Lett. 84, 2901 (2000).CrossRefGoogle Scholar
3Hashimoto, K. In Current Topics in Amorphous Materials: Physics and Technology, edited by Sakurai, Y., Hamakawa, Y., Masumoto, T., Shirae, K. and Suzuki, K. (Elsevier Science Publishers, 1993), p. 167.CrossRefGoogle Scholar
4Kawamura, Y., Shibata, V., Inoue, A. and Masumoto, T.: Workability of the supercooled liquid in the Zr65Al10Ni10Cu15 bulk metallic glass. Appl. Phys. Lett. 69, 1208 (1996).CrossRefGoogle Scholar
5Kawamura, Y., Shibata, T. and Inoue, A.: Superplastic deformation of Zr65Al10Ni10Cu15 metallic glass. Scripta Mater. 37, 431 (1997).CrossRefGoogle Scholar
6Nieh, T.G., Wadsworth, J., Liu, C.T., Ohkubo, T. and Hirotsu, Y.: Plasticity and structural instability in a bulk metallic glass deformed in the supercooled liquid region. Acta Mater. 49, 2887 (2001).CrossRefGoogle Scholar
7Lee, K.S., Ha, T.K., Ahn, S. and Chang, Y.W.: High temperature deformation behavior of the Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass. J. Non-Cryst. Solids 317, 193 (2003).CrossRefGoogle Scholar
8Sergueeva, A.V., Mara, N. and Mukherjee, A.K.: Mechanical response of Zr-based metallic glass. J. Non-Cryst. Solids 317, 169 (2003).CrossRefGoogle Scholar
9Kato, H., Kawamura, Y. and Inoue, A.: High tensile strength bulk glassy alloy Zr65Al10Ni10Cu15 prepared by extrusion of atomized glassy powder. Materials Trans. JIM 37, 70 (1996).CrossRefGoogle Scholar
10Kim, W.J., Ma, D.S. and Jeong, H.G.: Superplastic flow in a Zr65Al10Ni10Cu15 metallic glass crystallized during deformation in a supercooled liquid region. Scripta Mater. 49, 1067 (2003).CrossRefGoogle Scholar
11Kawamura, Y., Shibata, T., Inoue, A. and Masumotos, T.: Workability of the supercooled liquid in the Zr65Al10Ni10Cu15 bulk metallic glass. Acta Mater. 46, 253 (1998).CrossRefGoogle Scholar
12Kawamura, Y., Shibata, T. and Inoue, A.: Stress overshoot in stress–strain curves of Zr65Al10Ni10Cu15 metallic glass. Mater. Trans., JIM 40, 335 (1999).CrossRefGoogle Scholar
13Chu, J.P., Chiang, C.L., Mahalingam, T. and Nieh, T.G.: Plastic flow and tensile ductility of a bulk amorphous Zr55Al10Cu30Ni5 alloy at 700 K. Scripta Mater. 49, 435 (2003).CrossRefGoogle Scholar
14Reger-Leonhard, A., Heilmaier, M. and Eckert, J.: Newtonion flow of Zr55Cu30Al10Nl5 bulk metallic glassy alloys. Scripta Mater. 43, 459 (2000).CrossRefGoogle Scholar
15Taub, A.I. and Luborsky, F.E.: Creep, stress relaxation and structural change of amorphous alloys. Acta Metall. 29, 1939 (1981).CrossRefGoogle Scholar
16Busch, R., Kim, Y.J. and Johnson, W.L.: Thermodynamics and kinetics of the undercooled liquid and the glass transition of the Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 alloy. J. Appl. Phys. 77, 4039 (1995).CrossRefGoogle Scholar
17Gao, Y.L., Shen, J., Sun, J.F., Wang, G., Xing, D.W., Xian, H.Z. and Zhou, B.D.: Crystallization behavior of ZrAlNiCu bulk metallic glass with wide supercooled liquid region. Mater. Lett. 57, 1894 (2003).CrossRefGoogle Scholar
18van den Beukel, A. and Sietsma, J.: The glass transition as a free volume related kinetic phenomenon. Acta Mater. 38, 383 (1990).CrossRefGoogle Scholar
19He, G., Loser, W. and Eckert, J.: Microstructure and mechanical properties of the Zr66.4Cu10.5Ni8.7Al8Ta6.4 metallic glass-forming alloy. Scripta Mater. 48, 1531 (2003).CrossRefGoogle Scholar
20Waniuk, T.A., Busch, R., Masuhr, A. and Johnson, W.L.: Equilibrium viscosity of the Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass-forming liquid and viscous flow during relaxation, phase separation, and primary crystallization. Acta Mater. 46, 5229 (1998).CrossRefGoogle Scholar
21Bae, D.H., Lim, H.K., Kim, S.H., Kim, D.H. and Kim, W.T.: Mechanical behavior of a bulk Cu–Ti–Zr–Ni–Si–Sn metallic glass forming nano-crystal aggregate bands during deformation in the supercooled liquid region. Acta Mater. 50, 1749 (2002).CrossRefGoogle Scholar
22Zhang, Z.F., Eckert, J. and Schultz, L.: Difference in compressive and tensile fracture mechanisms of Zr59Cu20Al10Ni8Ti3 bulk metallic glass. Acta Mater. 51, 1167 (2003).CrossRefGoogle Scholar
23Hart, E.W.: Theory of the tensile test. Acta Metall. 15, 351 (1967).CrossRefGoogle Scholar
24Iwasaki, H., Mori, T., Mabuchi, M. and Higashi, K.: Microstructural evolution and plastic stability during superplastic flow in a 7475 aluminum alloy. Mater. Sci. Technol. 15, 180 (1999).CrossRefGoogle Scholar
25Kim, H.S.: Strengthening mechanisms of Zr-based devitrified amorphous alloy nanocomposites. Scripta Mater. 48, 43 (2003).CrossRefGoogle Scholar
26Lu, K. and Wang, J.T.: Activation energies for crystal nucleation and growth in amorphous alloys. Mater. Sci. Eng. A 133, 501 (1991).CrossRefGoogle Scholar