High Temperature Mechanical Behavior of Ti-45Al-8Nb and Its Cavity Evolution in Deformation

作者：Du, Zhihao^*; Zhang, Kaifeng; Jiang, Shaosong; Zhu, Ruican; Li, Shuguang

来源：Journal of Materials Engineering and Performance, 2015, 24(10): 3746-3754.

DOI：10.1007/s11665-015-1676-x

• cavity evolution
• constitutive model
• fracture morphology
• mechanical behavior
• TiAl alloy

The tensile property of a high Nb containing TiAl-based alloy (Ti-45Al-8Nb) was investigated in the temperature range of 900-1050 A degrees C and strain rate range of 1 x 10(-3) to 2.5 x 10(-2) s(-1). The results revealed that the yield stress decreased with increasing temperature and decreasing strain rate, while the tensile elongation increased with an increase in temperature and a decrease in strain rate. Hence, The minimum yield stress of 119.2 MPa and the maximum elongation of 237% were obtained at the temperature of 1050 A degrees C and strain rate of 1 x 10(-3) s(-1). Based on the experimental data, the activation energy of the alloy was calculated to be 360 kJ/mol. Moreover, the microstructure and the fracture morphology of the specimens were observed, and the results revealed that the distribution of cavities was related to deformation parameters and the fracture mode was typically dimple-type.

• 出版日期2015-10
• 单位哈尔滨工业大学