摘要
在温度1123～1273K和应变速率5×10-5～5×10-3s-1范围内,研究了具有复相组织的Ti-47Al-1.5Cr-0.5Mn-2.8Nb合金拉伸性能的应变速率敏感性.发现提高应变速率或降低温度均可使合金的延伸率下降、强度增加,不同温度下拉伸强度与应变速率对数之间存在线性关系;利用热激活理论不仅解释了这一关系,还获得了应变速率方程,指出控制合金拉伸形变的微观机制是原子扩散过程.
Tensile properties of Ti 47Al 1.5Cr 0.5Mn 2.8Nb alloy with duplex microstructure were tested at 1123～1273 K and strain rates 5×10 -5 ～5×10 -3 s -1 . It was found that an increase of the strain rate or a decrease of the temperature resulted in a decrease of the elongation and an increase of the strength. Furthermore, an approximate linear relationship was found between strength or flow stress and the logarithm of the strain rate at different temperatures. The thermal activation theory interpreted such a relationship and derived strain rate equation. It pointed to a controlling mechanism of atomic diffusion in nature, which was identified as dislocation climb by transmission electron microscopy observation.
出处
《上海交通大学学报》
CSCD
北大核心
2000年第3期329-333,共5页
Journal of Shanghai Jiaotong University
基金
国家自然科学基金!资助项目 ( 5 93 3 10 11)
关键词
金属间化合物
TIAL合金
位错
力学性能
应变速率
intermetallics
TiAl alloys
tensile properties
strain rate
thermal activation
dislocation
