5083铝合金高温塑性变形行为

High-temperature plastic deformation behavior of 5083 aluminum alloy

采用高温拉伸试验方法研究了5083铝合金在温度为450℃,应变速率为1×10^(-2)~1×10^(-4) s^(-1)下的塑性变形行为,通过微观组织分析研究了高温拉伸过程中的塑性变形行为。结果表明,450℃时,5083铝合金的伸长率随应变速率的降低呈现先增大后减小的趋势。当应变速率为1×10^(-3) s^(-1)时,伸长率达到最大139.2%。当温度为450℃时,随应变速率的降低,流动应力逐渐下降。在保温20~100 min时间内,从30 min时开始发生再结晶,随着时间的延长,再结晶晶粒数量逐渐增多。在应变速率和保温时间的共同作用下,20 min时开始发生动态再结晶,40~100 min晶粒开始逐渐长大。细小晶粒的增多使得伸长率增大,但随着保温时间的延长,细小晶粒长大,伸长率下降。

The plastic deformation behavior of 5083 aluminum alloy at 450℃and strain rate of 1×10^(-2)-1×10^(-4) s^(-1) was studied by high-temperature tensile test method.The plastic deformation behavior during high-temperature tension process was studied by microstructure analysis.The results show that the elongation of 5083 aluminum alloy increases first and then decreases with the decrease of strain rate at 450℃.When the strain rate is 1×10^(-3) s^(-1),the elongation reaches the maximum of 139.2%.When the temperature is 450℃,the flow stress decreases gradually with the decrease of strain rate.During the holding time of 20-100 min,the recrystallization begins at 30 min,and with the extension of time,the number of recrystallization grains increases gradually.Under the joint action of strain rate and holding time,dynamic recrystallization begins at 20 min,and the grains begin to grow gradually in 40-100 min.The increase of fine grains makes the elongation increase,but with the extension of holding time,the fine grains grow and the elongation decreases.