Failure Behaviour and Energy Adsorption in Gum Metal (Ti-36Nb-2Ta-3Zr-O)
Recently, there has been much interest in the development of low modulus, biocompatible beta titanium alloys such as Gum metal (Ti-36Nb-2Ta-3Zr-0. 30 wt％). Diffraction and TEM evidence have suggested that the orthorhombic (a) martensite can been induced at high stresses and that this is the source of the superelasticity observed,although other authors continue to insist that the alloys shear in a manner consistent with ideal strength. Twinning and the omega phase may also be involved. However, no data have previously been produced on the fatigue and high strain rate behaviour of Gum metal,and this is presented here. Significantly,a value of stress ratio R=0. 3 un-notched high cycle fatigue strength (runout life) in excess of 550 MPa is found. The fracture surfaces shows relief characteristic of lath (martensite) activity. In addition,aging treatments are examined to improve the strength of Gum metal to over 1. 5GPa whilst retaining ductility and energy adsorption by introducing a very fine distribution of alpha phase. The source(s) available for nucleation of this alpha phase will be discussed in light of the ideal shear and omega hypotheses.
Gum metal metastable beta alloys martensitic trans formation fatigue high strain rate testing
Nicholas G. Jones Russell J. Tailing Trevor C. Lindley David Dye
Department of Materials, Imperial College London, London, SW7 2AZ, UK
国际会议
The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)
北京
英文
1169-1173
2011-06-19（万方平台首次上网日期，不代表论文的发表时间）