形变参数对GH4169合金热变形行为的影响

Influence of deformation parameters on hot deformation behavior of GH4169 superalloy

利用Gleeble-1500热模拟试验机,研究了GH4169合金在变形温度为900～1100℃、应变速率为0.1 s-1、1 s-1、20 s-1、最大变形量高达70%条件下的高温变形行为,建立了GH4169合金的高温变形流动应力模型,分析了变形工艺参数对合金晶粒再结晶的影响规律。结果表明:随变形温度的降低和应变速率的增加,合金变形抗力显著增加;当变形量超过临界变形量时,随着变形量增加或变形温度的提高,合金的再结晶程度逐渐增加;然而,变形速率的变化,对该合金再结晶影响较为复杂。

Flow behavior of isothermally compressed GH4169 alloy in the deformation temperature range from 900 ℃ to 1100 ℃,the strain rate range from 0.1 to 20 s-1 and the maximum deformation of 70% was investigated on a thermomechanical simulator Gleeble-1500.Meanwhile,a flow stress model was established.The microstructural parameters such as fraction of recrystallization and grain sizes were analyzed quantitatively.The results show that the flow stress of GH4169 alloy significantly increases with the deformation temperature decreasing and the increasing of strain rate.The flow stress changes differently with the increase of the strain under different temperatures and strain rates.The increasing of temperature and strain can promote the nucleation and growth for GH4169 alloy recrystallization.While the effect of increasing strain rate on fraction of recrystallizaiton is complex.