2099合金热变形加工图研究

采用Gleeble-1500热模拟试验机对2099合金进行等温热压缩试验,研究了基于动态材料模型的加工图,分析了该合金在变形温度为300~500℃,应变速率为0.001~10 s-1范围内安全区和失稳区的组织特征,并对其热加工工艺进行优化。结果表明,2099合金的加工失稳区主要位于300~420℃,0.001~0.02 s-1和300~500℃,0.562~10 s-1范围内。失稳区组织出现了局部流变、局部剪切、局部流变+局部剪切等特征;安全区组织以动态回复、动态回复+动态再结晶为主要特征。合金热加工工艺优化为:真应变<1.1时,工艺参数为380~420℃,0.025~1 s-1;真应变>3.4时,工艺参数为420~500℃,0.001~0.562 s-1。

Processing Map of 2099 Alloy Deformed at High Temperature

A processing map based on dynamic material modeling of 2099 alloy was investigated by isothermal compression tests on a Gleeble-1500 machine. Microstructure characteristics of safety areas and instability areas in the temperature range of 300~500 oC, strain rate of 0.001~10 s-1 of 2099 alloy were analyzed. And the optimized processing parameters were also proposed. Results show that the instability areas of 2099 mainly locate in the regions of 300~420 oC, 0.001~0.02 s-1 and 300~500 oC, 0.562~10 s-1. Microstructure in the instability areas displays local plastic deformation, local adiabatic shear and local plastic deformation + local adiabatic shear. The main deformation mechanisms in safety areas are dynamic recovery and dynamic recovery + dynamic recrystallization. The optimized processing parameters can be summarized as that when the true strain is less than 1.1, the processing parameters are 380~420 oC and 0.025~1 s-1; when the true strain is over 3.4, the processing parameters are 420~500 oC, 0.001~0.562 s-1.