3003铝合金动态再结晶实验研究

Experimental Research on Dynamic Recrystallization of 3003 Aluminum Alloy

采用Gleeble-1500热模拟试验机对3003铝合金进行变形温度为300～500℃、应变速率为0.01～10.0s-1的高温等温压缩实验,由真应力-真应变曲线计算应变硬化速率,并采用截线法测量热压缩后平均晶粒尺寸,结果表明:3003铝合金动态再结晶临界应变εc随着Z参数的增大而提高,合金发生动态再结晶的临界条件为:ε>εc=7.28×10-5 Z0.1661;动态再结晶的平均晶粒尺寸随温度的升高、应变速率的减小而增大,其关系为:lndave=-0.0824lnZ+4.9532;在实验条件下,该合金具有正的应变速率敏感性,随变形温度的降低和应变速率的增大,合金进入稳态流变阶段时所对应的真应力值逐渐增大,并且峰值应力随动态再结晶平均晶粒尺寸的减小而增大,符合Hall-Petch关系:lnσm=-0.9378lndave+6.5232。

The 3003 aluminum alloy was deformed by isothermal compression in the range of deformation temperature 300-500℃ at strain rate 0.01-10.0s-1 using Gleeble-1500 thermal simulator.The strain-hardening rate could be obtained from true stress-true strain curves,and the recrystallization average grain size was measured using the intercept method.The results show that the critical strain εc increases with parameter Z increasing,the critical conditions for onset of dynamic recrystallization（DRX） is εεc=7.28×10-5Z0.1661.The average recrystallization grain size increases as deformation temperature increases and the strain rate decreases,which can be described as lndave=-0.0824lnZ＋4.9532.The investigated alloy is sensitive to positive strain rate under the experimental conditions.The true stress increases as the deformation temperature decreases and the strain rate increases.The peak stress increases with the average recrystallization grain size decreasing,which meets with the law of Hall-Petch： lnσm=-0.9378lndave＋6.5232.