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Phase selection and mechanical properties of a directionally solidified Cr–20Nb–40Ti alloy

Published online by Cambridge University Press:  25 November 2015

Yunlong Xue
Affiliation:
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 Shanxi, China
Shuangming Li*
Affiliation:
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 Shanxi, China
Hong Zhong
Affiliation:
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 Shanxi, China
Kewei Li
Affiliation:
College of Material Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 Shanxi, China
Hengzhi Fu
Affiliation:
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 Shanxi, China
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

By combining the techniques of directional solidification and coating Y2O3, a Cr–20Nb–40Ti alloy was manufactured successfully with various growth rates. The revolution of microstructures and corresponding mechanical properties was discussed to develop the Cr2Nb based alloys with good combination of mechanical properties. The results show that the favorable growth dynamics of plane (220) of Laves phase Cr2Nb was observed with the increase of growth rate. Phase selection took place in microstructures evolved from the primary Cr2Nb, via the dendrite-like eutectic Cr2Nb/β-Ti, and finally to the primary β-Ti, with increasing the growth rate from 5 to 200 μm/s. Based on the coupled zone of eutectic, the competitive growth of solidified phases in the directionally solidified Cr–20Nb–40Ti alloy was elucidated. In addition, the mechanical properties of alloy depended on the growth rate, and the fracture toughness of the alloy reached 16.50 MPa m1/2 at 200 μm/s, much larger than 1.40 MPa m1/2 for single-phase Cr2Nb.

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Articles
Copyright
Copyright © Materials Research Society 2015 

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References

REFERENCES

Li, C.L., Kuo, J.L., Wang, B., and Wang, R.: Effects of X (V, W, Mo, Hf, Ta, Zr) additions on the ideal cleavage fracture of Cr2Nb: First-principles determination. Intermetallics 18, 65 (2010).Google Scholar
Zhang, W., Yu, R., Du, K., Cheng, Z.Y., Zhu, J., and Ye, H.Q.: Undulating slip in Laves phase and implications for deformation in brittle materials. Phys. Rev. Lett. 106, 165505 (2011).Google Scholar
Yang, Z.Q., Chisholm, M.F., Yang, B., Ma, X.P., Wang, Y.J., and Zhuo, M.J.: Role of crystal defects on brittleness of C15 Cr2Nb Laves phase. Acta Mater. 60, 2637 (2012).Google Scholar
Ma, L., Fan, T.W., Tang, B.Y., Peng, L.M., and Ding, W.J.: Ab initio study of I2 and T2 stacking faults in C14 Laves phase MgZn2. Eur. Phys. J. B 86, 188 (2013).Google Scholar
Aufrecht, J., Leineweber, A., Senyshyn, A., and Mittemeijer, E.J.: The absence of a stable hexagonal Laves phase modification (NbCr2) in the Nb-Cr system. Scr. Mater. 62, 227 (2010).Google Scholar
Xue, Y.L., Li, S.M., Zhong, H., and Fu, H.Z.: Characterization of fracture toughness and toughening mechanisms in Laves phase Cr2Nb based alloys. Mater. Sci. Eng., A 638, 340 (2015).Google Scholar
Li, K.W., Li, S.M., Xue, Y.L., and Fu, H.Z.: Microstructure characterization and mechanical properties of a Laves-phase alloy based on Cr2Nb. Int. J. Refract. Met. Hard Mater. 36, 154 (2013).Google Scholar
Lu, S.Q., Zheng, H.Z., Deng, L.P., and Yao, J.: Effect of silicon on the fracture toughness and oxidation behavior of hot pressed NbCr2 alloys. Mater. Des. 51, 432 (2013).Google Scholar
Xiao, X., Lu, S.Q., Hu, P., Huang, M.G., Nie, X.W., and Fu, M.W.: The effect of hot pressing time on the microstructure and properties of Laves phase NbCr2 alloys. Mater. Sci. Eng., A 485, 80 (2008).Google Scholar
Davidson, D.L. and Chan, K.S.: Microstructural and fracture characterization of Nb-Cr-Ti mechanically alloyed materials. Metall. Mater. Trans. A 33, 401 (2002).Google Scholar
Davidson, D.L., Chan, K.S., and Anton, D.L.: The effects on fracture toughness of ductile-phase composition and morphology in Nb-Cr-Ti and Nb-Si in situ composites. Metall. Mater. Trans. A 27, 3007 (1996).Google Scholar
Chan, K.S., Davidson, D.L., and Anton, D.L.: Fracture toughness and fatigue crack growth in rapid quenched Nb-Cr-Ti in situ composites. Metall. Mater. Trans. A 28, 1797 (1997).Google Scholar
Chan, K.S. and Davidson, D.L.: Improving the fracture toughness of constituent phases and Nb-based in situ composites by a computational alloy design approach. Metall. Meter. Trans. A 34, 1833 (2003).Google Scholar
Kazantzis, A.V., Aindow, M., Jones, I.P., Triantafyllidis, G.K., and Hosson, J.: The mechanical properties and the deformation microstructures of the C15 Laves phase Cr2Nb at high temperatures. Acta Mater. 55, 1873 (2007).Google Scholar
Kim, W.Y., Tanaka, H., Kasama, A., and Hanada, S.: Microstructure and room temperature fracture toughness of Nbss/Nb5Si3 in situ composites. Intermetallics 9, 827 (2001).Google Scholar
Nie, G., Ding, H.S., Chen, R.R., Guo, J.J., and Fu, H.Z.: Microstructural control and mechanical properties of Ti-47Al-2Cr-2Nb alloy by directional solidification electromagnetic cold crucible technique. Mater. Des. 39, 350 (2012).Google Scholar
Su, L.F., Jia, L.N., Feng, Y.B., Zhang, H.R., Yuan, S.N., and Zhang, H.: Microstructure and room-temperature toughness of directionally solidified Nb-Si-Ti-Cr-Al-Hf alloy. Mater. Sci. Eng., A 560, 672 (2013).Google Scholar
Cheng, G.M. and He, L.L.: Microstructure evolution and room temperature deformation of a unidirectionally solidified Nb-22Ti-16Si-3Ta-2Hf-7Cr-3Al-0.2Ho (at.%) alloy. Intermetallics 19, 196 (2011).Google Scholar
Fujita, M., Kaneno, Y., and Takasuigi, T.: Phase field and room-temperature mechanical properties of C15 Laves phase in Nb-Hf-Cr and Nb-Ta-Cr alloy systems. J. Alloys Compd. 424, 283 (2006).Google Scholar
Shah, D.M., Anton, D.L., Pope, D.P., and Chin, S.: In-situ refractory intermetallic-based composites. Mater. Sci. Eng., A 192193, 658 (1995).Google Scholar
Ji, C.C., Li, J.G., Ma, W.Z., and Zhou, Y.H.: Preparation of Terfenol-D with precise 〈110〉 orientation and observation of the oriented growth crystal morphology. J. Alloys Compd. 333, 291 (2002).Google Scholar
Trebin, H.R. and Gumbsch, P.: Interatomic potentials and the simulation of fracture: C15 NbCr2. Int. J. Fract. 139, 517 (2006).Google Scholar
Kurz, W. and Fisher, D.J.: Fundamentals of Solidification, 4th ed. (Trans Tech Publications Ltd, Uetikon-Zuerich, Switzerland, 1998); p. 89.Google Scholar
Herlach, D.M., Galenko, P.K., and Holland-Moritz, D.: Metastable Solids from Undercooled Melts (Elsevier, Amsterdam, Netherlands, 2007); p. 335.Google Scholar
Wang, N., Kalay, Y.E., and Trivedi, R.: Eutectic-to metallic glass transition in the Al-Sm system. Acta Mater. 59, 6604 (2011).Google Scholar
Takeyama, M. and Liu, C.T.: Microstructure and mechanical properties of Laves-phase alloys based on Cr2Nb. Mater. Sci. Eng., A 132, 61 (1991).Google Scholar
Sekido, N., Kimura, Y., Miura, S., Wei, F.G., and Mishima, Y.: Fracture toughness and high temperature strength of unidirectionally solidified Nb-Si binary and Nb-Ti-Si ternary alloys. J. Alloys Compd. 425, 223 (2006).Google Scholar
Lee, B., Liaw, P.K., Liu, C.T., and Chou, Y.T.: Cracking in Cr-Cr2Nb eutectic alloys due to thermal stresses. Mater. Sci. Eng., A 268, 184 (1999).Google Scholar
Bhowmik, A. and Stone, H.J.: Microstructure and mechanical properties of tow-phase Cr-Cr2Ta alloys. Metall. Mater. Trans. A 43, 3283 (2012).Google Scholar
Choe, H., Schneibel, J.H., and Ritchie, R.O.: On the fracture and fatigue properties of Mo-Mo3Si-Mo5SiB2 refractory intermetallic alloys at ambient to elevated temperatures. Metall. Mater. Trans. A 34, 225 (2003).Google Scholar
Li, Z. and Peng, L.M.: Microstructural and mechanical characterization of Nb-based in situ composites from Nb-Si-Ti ternary system. Acta Mater. 55, 6573 (2007).Google Scholar