Abstract
The dynamic mechanical properties and failure behavior of rolled and heat treated Ti-4.5Mo-5.1Al-1.8Zr-1.1Sn-2.5Cr-2.9Zn alloys were studied. The results show that after multi-pass rolling at 880℃, a duplex microstructure consisting of β matrix and non-uniformly distributed "equiaxed+strip" α phase is obtained, and the microstructure is composed of β matrix and fully equiaxed α phase after the heat treatment at 895℃ for 0.5 h. The results of dynamic compression tests under different strain rates of 3100~3800 s-1 show that the dynamic compression strength of rolled titanium alloys is 200~400 MPa higher than that of heat treated titanium alloys, with a maximum value of 2133 MPa, but the critical fracture strain is obviously lower, with a maximum value of only 10.8%. Although the dynamic compression strength of titanium alloys decreases after heat treatment, the critical fracture strain can reach 23.6%, showing better matching feature of strength and plasticity. Further study finds that the characteristic of high dislocation density and inhomogeneous structure distribution of rolled titanium alloys results in bifurcated adiabatic shear bands during dynamic compression tests. The fracture surfaces of rolled titanium alloys show two characteristics: smooth zone and dimple zone, indicating that the fracture mechanism is brittle fracture+ductile fracture, while that of heat treated titanium alloys is mainly dimple zone, indicating that the fracture mechanism is ductile fracture. The research provides theoretical and technical support for the engineering preparation and application of the new alloy.
| Translated title of the contribution | Dynamic Mechanical Properties and Failure of Ti-4.5Mo-5.1Al-1.8Zr-1.1Sn-2.5Cr-2.9Zn Alloy |
|---|---|
| Original language | Chinese (Traditional) |
| Pages (from-to) | 1235-1241 |
| Number of pages | 7 |
| Journal | Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering |
| Volume | 49 |
| Issue number | 4 |
| Publication status | Published - 1 Apr 2020 |