摘要
采用Gleeble-3800热模拟机对新型镍基高温合金GH4700在变形温度1 120～1 170℃,应变速率0.01～1 s-1下的热变形行为和组织演变进行了研究,建立了合金的热变形本构模型。结果表明:合金的流变应力随着应变速率的减小和变形温度的升高而降低,曲线表现出动态再结晶特征;采用考虑应变量的双曲正弦模型能较好地反映合金在热变形过程中流变应力的变化规律;GH4700合金在热压缩变形过程中,降低应变速率和提高变形温度均有利于动态再结晶的发生。
The hot deformation behavior and microstructure evolution of nickel-based superalloy GH4700 were studied in the temperature rang from 1120 ℃to 1170 ℃ and the strain rate from 0.01 s-1 to 1 s-1by Gleeble-3800 hot simulator. The constitutive equation of hot process for the alloy was established. The results show that the rheological stresses decrease with the increase of deformation temperature and the decrease of strain rate. The curves of stress and strain show the dynamic recrystallization features. The hyperbolic sine model including strain can well reflect the change law of flow stress of superalloy GH4700 in hot deformation process. The dynamic recrystallization of superalloy GH4700 occurs easily with decreasing strain rate and increasing deformation temperature during hot compressive deformation.
出处
《铸造技术》
CAS
北大核心
2013年第8期953-957,共5页
Foundry Technology
基金
国家"973"计划资助项目(2012CB723905)
山西省自然科学基金资助项目(2012011021-5)
关键词
高温合金
流变行为
本构模型
动态再结晶
superalloy alloy
flow behavior
constitutive equation
dynamic recrystallization
