Dwell and Normal Cyclic Fatigue Behaviours of Ti60 Alloy

doi:10.1016/j.jmst.2013.10.010

Abstract

Abstract: An experimental study of dwell and normal cyclic fatigue behaviours was carried out using specimens from a Ti60 forging with a bimodal microstructure. Apparent decrease in the fatigue life was found under dwell fatigue condition as compared to that under normal cyclic condition. Strain produced in each cycle in dwell fatigued specimens was observed larger than that in its normal cyclic-fatigued counterparts. Interior crack initiation was found in most dwell fatigued specimens as compared to the subsurface crack initiation under normal cyclic fatigue condition. Flat and bright facets were found at crack initiation sites in both cases. The facet density is higher in dwell condition, which is consistent with the crystal orientation and Schmid factors analysis of α grains around secondary cracks using electron back-scattered diffraction (EBSD) methods. Dwell loading favours cleavage in α grains with their basal plane normals aligned no more than 15° to the loading axis, which may account for its lower fatigue life according to the present study.

Key words: Ti60 alloy, Dwell fatigue, Quasi-cleavage facet, Electron back-scattered diffraction (EBSD), Strain accumulation

Yang Lina, Liu Jianrong, Tan Jun, Chen Zhiyong, Wang Qingjiang, Yang Rui. Dwell and Normal Cyclic Fatigue Behaviours of Ti60 Alloy[J]. J. Mater. Sci. Technol., 2014, 30(7): 706-709.

References

[1] M.R. Bache,Int. J. Fatigue,25 (2003), pp.1079–1087
[2] M.R. Bache,M. Cope,H.M. Davies,W.J. Evans,G. Harrison,Int. J. Fatigue,19 (1997), pp.83–88
[3] K. Kirane,S. Ghosh,Int. J. Fatigue,30 (2008), pp.2127–2139
[4] J.E. Hack,G.R. Leverant,Scripta Metall.,14 (1980), pp.437–441
[5] M.R. Bache,W.J. Evans,V. Randle,R.J. Wilson,Mater. Sci. Eng. A,257 (1998), pp.139–144
[6] F. McBagonluri,E. Akpan,C. Mercer,W. Shen,W.O. Soboyejo,Mater. Sci. Eng. A,405 (2005), pp.111–134
[7] C.C. Wojcik,K.S. Chan,D.A. Koss,Acta Metall.,36 (1988), pp.1261–1270
[8] G. Tarun,Int. J. Fatigue,21 (1999), pp.55–76
[9] M.R. Bache,W.J. Evans,H.M. Davies,J. Mater. Sci.,32 (1997), pp.3435–3442
[10] X. Wang,P. Vo,M. Jahazi,S. Yue,Metall. Mater. Trans. A,38 (2007), pp.831–839
[11] Z. Song,D. Hoeppner,Int. J. Fatigue,11 (1989), pp.85–90
[12] V. Sinha,J.E. Spowart,M.J. Mills,J.C. Williams,Metall. Mater. Trans. A,37 (2006), pp.1507–1518
[13] P. Lefranc,V. Doquet,M. Gerland,C. Sarrazin-Baudoux,Acta Mater.,56 (2008), pp.4450–4457
[14] M. Gerland,P. Lefranc,V. Doquet,C. Sarrazin-Baudoux,Mater. Sci. Eng. A,507 (2009), pp.132–143
[15] V. Sinha,M. Mills,J. Williams,J. Mater. Sci.,42 (2007), pp.8334–8341
[16] F. Bridier,P. Villechaise,J. Mendez,Acta Mater.,56 (2008), pp.3951–3962
[17] E. Uta,N. Gey,P. Bocher,M. Humbert,J. Gilgert,J. Microsc.,233 (2009), pp.451–459
[18] I. Bantounas,T.C. Lindley,D. Rugg,D. Dye,Acta Mater.,55 (2007), pp.5655–5665
[19] M. Es-Souni,Mater. Charact.,46 (2001), pp.365–379
[20] S. Suri,T. Neeraj,G.S. Daehn,D.H. Hou,J.M. Scott,R.W. Hayes,M.J. Mills,Mater. Sci. Eng. A,234 (1997), pp.996–999
[21] T. Neeraj,D.H. Hou,G. Daehn,M. Mills,Acta Mater.,48 (2000), pp.1225–1238
[22] J.E. Hack,G.R. Leverant,Metall. Trans. A,13 (1982), pp.1729–1738
[23] R.W. Evans,B. WilshireCreep of Metals and Alloys,Institute of Metals Publishers,Swansea (1985), p.314
[24] B. Sander,D. Raabe,Mater. Sci. Eng. A,479 (2008), pp.236–247
[25] F. Torster,C. Andres,G. Lutjering,A. Gysler,Z. Metallk.,90 (1999), pp.174–181
[26] N. Gey,P. Bocher,E. Uta,L. Germain,M. Humbert,Acta Mater.,60 (2012), pp.2647–2655
[27] M. Bache,W. Evans,B. Suddell,F. Herrouin,Int. J. Fatigue,23 (2001), pp.153–159
[28] M.G. Glavicic,B.B. Bartha,S.K. Jha,C.J. Szczepanski,Mater. Sci. Eng. A,513 (2009), pp.325–328
[29] A. Stroh,Math. Phys. Sci.,223 (1954), p.404
[30] M. Bache,H. Davies,W. Evans,Adv. Fract. Res.,9 (1997), pp.351–358
[31] F.K. HaBasis of Fracture Physics,Science Press,Beijing (2000), p.
[32] W. Evans,M. Bache,Int. J. Fatigue,16 (1994), pp.443–452
[33] R. Morrissey,D. McDowell,T. Nicholas,Int. J. Fatigue,23 (2001), pp.55–64
[34] M. Savage,T. Neeraj,M. Mills,Metall. Mater. Trans. A,33 (2002), pp.891–898