摘要
建立了Mg-9Li-3Al-2.5Sr合金在不同热变形条件下的本构方程,并研究了热变形条件对材料显微组织的影响。结果表明,热变形过程中合金的流变应力与变形速率和变形温度之间的关系可以用本构方程Z=9.23×1011×[sinh(0.002 472 52σ)]3.75描述。材料变形过程中的稳态流变应力可以用双曲正弦函数描述。在高温低应变速率下,当三角晶界处应力集中的速率大于晶界扩散和滑移速率时,将产生裂纹。裂纹不断萌生扩展,最终导致材料失稳。
The constitutive equation of the alloy Mg-9Li-3Al-2.5Sr under different deformation conditions was established,and the effect of hot deformation conditions on the microstructures of the alloy was investigated. The results show that the relationship between the flow stress and the deformation rate, deformation temperature during hot deformation can be described by the constitutive equation Z=9.23×1011×[sinh（0.002 472 52σ）]3.75. The steady flow stress during the deformation can be described by sinh function. The crack will appear when the rate of stress concentration at the triangle grain boundary exceeds the rate of the grain boundary diffusion and slip under high temperature and low strain rate. The crack extends continually and in the end the material becomes unstability.
出处
《铸造技术》
CAS
北大核心
2014年第7期1411-1413,共3页
Foundry Technology
