变形条件对2124铝合金超厚板流变行为与显微组织的影响

在Gleeble-1500热/力机上进行了变形条件对2124铝合金超厚板流变行为与显微组织的影响规律的系列实验研究,得到了不同变形条件下2124铝合金超厚板高温压缩成形过程中的流变曲线。实验结果表明,2124铝合金在0.01s-1~1s-1范围内,高温压缩变形过程存在近稳态流变特征,近稳态流变应力随着应变速率的降低和变形温度的升高而降低。当应变速率为10s-1时,真应力-真应变曲线出现锯齿状,说明合金发生动态再结晶现象。利用OM和TEM分别研究了变形温度、应变速率、应变量对2124铝合金高温压缩变形显微组织的影响,在此基础上,分析并建立了2124铝合金热压缩变形发生动态再结晶的临界条件。

Influence of deformation conditions on rheological behavior and microstructure of 2124 aluminum super-thick strip

Series experimental researches about the influence of deformation conditions on rheological behavior and microstructure of 2124 aluminum super-thick strip were conducted with Gleeble-1500 Thermal-Mechanical Simulation Tester. Experimental results show that during high temperature and different strain rate between 0. 01s~(-1)～1s~(-1), the deformation behavior of 2124 aluminum takes on quasi-steady state rheological characteristic Its rheological stress decreases with the increase of deformation temperature and the decrease of strain rate. When the strain rate is higher than 10s~(-1), the true stress and true strain curve fluctuates in saw-tooth, which indicates dynamic recrystallization phenomena occur in such alloy. The OM and TEM were both used to analyze the influence of deformation temperature, strain rate and strain value on the microstructure of 2124 aluminum. The critical conditions for dynamic recrystallization were established based on above analysis.