CP-Ti Processed for Multiple Passes by ECAP at Room Temperature

Abstract:

A series of experiments were conducted to evaluate the feasibility that commercially pure titanium (CP-Ti) was pressed for multiple passes by equal channel angular pressing (ECAP) at room temperature. Samples of CP-Ti were processed at room temperature using the dies with channel angles of 90° and 120°, respectively. First, each billet was processed 4 passes by ECAP using a die with an angle of 120° and a ram speed of 0.5mm s-1. And in order to eliminate residual stress, immediate annealing at 473 K for an hour was conducted between two adjacent passes. Second, CP-Ti was successfully processed by ECAP for up to 8 passes using the same die and a ram speed of 2 mm s-1 by controlling the flow of metal. Finally, CP-Ti was successfully achieved using a conventional die with an angle of 90° between the channels at room temperature. Each billet was processed for two passes with a ram speed of 26 mm s-1. These experiments show that CP-Ti may be processed by ECAP at room temperature and special attention was paid on improvements in the yield stress, ultimate strength and micro-hardness of ECAPed-Ti that are slightly higher than the improvements attained after pressing at elevated temperatures.

• Periodical: Materials Science Forum (Volumes 667-669)
• Pages: 779-784
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.667-669.779
• Online since: December 2010
• Authors: Xi Rong Yang, Xi Cheng Zhao, Xiao Yan Liu
• Keywords: Commercial Pure Titanium (CP-Ti), Equal-Channel Angular Pressing (ECAP), Room Temperature

References

[1] Y. Zhu, T. Lowe, T.G. Langdon. Scripta Mater. Vol. 51(2004), p.825.

[2] A. Balyanov, J. Kutnyakova, N.A. Amirkhanova, V.V. Stolyarov, R.Z. Valiev, X.Z. Liao, Y.H. Zhao, Y.B. Jiang, H.F. Xu, T.C. Lowe, Y.T. Zhu, Scrpita Mater. Vol. 51(2004) 225.

[3] V.V. Stolyarov, R.Z. Valiev, Y.T. Zhu, Appl. Phys. Lett. Vol. 88 (2006) 041905.

[4] S L Semiatin, V M Segal, R E Goforth, N D Frey and D P DeLo, Metal. Mater. Trans. Vol. 30A(1999), p.1425.

[5] V.V. Stolyarov, Y.T. Zhu, T.C. Lowe, R.K. Islamgaliev and R.Z. Valiev, NanoStruct. Mater. Vol. 11(1999), p.947.

[6] V.V. Stolyarov, Y.T. Zhu, I.V. Alexandrov, T.C. Lowe, R.Z. Valiev, Mater. Sci. Eng. Vol. 299A (2001) 59.

[7] W.J. Kim, C.Y. Hyun and H.K. Kim, Scripta Mater. Vol. 54(2006), p.1745.

[8] A. Yu. Vinogradov, V.V. Stolyarov, S. Hashimoto and R.Z. Valiev, Mater. Sci. Eng. Vol. 318A(2001), p.163.

[9] D.H. Shin, I. Kim, J. Kim, Y.S. Kim, S.L. Semiatin, Acta Mater. Vol. 51(2003), p.983.

[10] I. Kim, J. Kim, D.H. Shin, X.Z. Liao, Y.T. Zhu, Scripta Mater. Vol. 48 (2003), p.813.

[11] V.V. Stolyarov, Y. T. Zhu, I. V. Alexandrov, T. C. Lowe, R. Z. Valiev，Mater. Sci. Eng. Vol. 299A (2001), p.59.

[12] I. Kim, J. Kim, D.H. Shin, C.S. Lee, S.K. Hwang, Mater. Sci. Eng. Vol. 342A (2003), p.302.

[13] G.I. Raab, E.P. Soshnikova, R.Z. Valiev, Mater. Sci. Eng. Vol. 387–389A(2004), p.674.

[14] Y. Iwahashi, J. Wang, Z. Horita, M. Nemoto, T.G. Langdon, Scripta Mater. Vol. 35 (1996), p.143.

[15] X.C. Zhao, W.J. Fu, X.R. Yang and T.G. Langdon, Scripta Mater. Vol. 59 (2008), p.542.

[16] X.R. Yang, X.C. Zhao, W.J. Fu, Rare Metal Mat. Eng. Vol. 38( 2009), p.955.

[17] X.C. Zhao, X.R. Yang, X.Y. Liu, X.Y. Wang, T. G. Langdon, Mater. Sci. Eng. Vol. 527A(2010), p.6335.

[18] R.Z. Valiev, R.K. Islamgaliev, I.V. Alexandrov, Prog. Mater. Sci. Vol. 45(2000), p.103.