Ageing behavior of Ti-6Cr-3Sn beta titanium alloy

作者：Wadood A^*; Inamura T; Hosoda H; Miyazaki S

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2011, 530: 504-510.

DOI：10.1016/j.msea.2011.10.009

• Ti-6Cr-3Sn
• Ageing
• Mechanical Properties
• Shape memory effect
• Pseudoelasticity

In this study, the effect of ageing treatment on mechanical, shape memory and pseudoelastic properties of our recently developed metastable beta Ti-6Cr-3Sn alloy was investigated for engineering applications. Solution-treated Ti-6Cr-3Sn alloy was aged at 373 K, 473 K. 573 K and 673 K using vacuum-sealed quartz tubes for 3.6 ks followed by water quenching. Shape memory effect, fracture strain and hardness were improved by ageing at 373 K most probably due to fine scale isothermal omega (omega) phase precipitation. However for samples aged at 473 K, 573 K and 673 K, fracture strain (2%, 2% and 4%, respectively) was drastically reduced, yield stress (440 MPa, 580 MPa and 490 MPa, respectively) and hardness (HV329, HV450 and HV457, respectively) were drastically increased as compared to solution-treated and aged at 373 K conditions with no pseudoelastic response. This brittle behavior was due to increase in the amount of isothermal omega phase precipitation as compared to 373 K ageing conditions. It is concluded that Ti-6Cr-35n alloy in solution-treated and aged at 373 K has potential as shape memory and pseudoelastic materials applications with excellent strength-ductility correspondence. However mechanical, shape memory and pseudoelastic properties were drastically deteriorated by ageing at 473 K, 573 K and 673 K due to increase in the amount of isothermal omega (omega) phase precipitation as compared to 373 K ageing conditions.

• 出版日期2011-12-15