摘要
基于加工图技术研究了GH4742合金在950~1160℃、0.001~1 s^(-1)条件下的热变形行为,分析了功率耗散效率和失稳参数对变形热力参数的动态响应特征,构建了基于动态材料模型的功率耗散图和失稳图,进一步获得了合金在不同应变下的加工图。结果表明,合金的功率耗散效率和失稳参数对变形热力参数较敏感。功率耗散效率随应变速率的降低和变形温度的升高呈增加趋势;在低变形温度和高应变速率时,失稳参数总体较小。热变形失稳参数窗口大致在变形温度950~20(lgε·+54)℃,应变速率0.001~1 s^(-1)范围,相对应的主要失稳现象为绝热剪切和局部流动。过渡组织变形参数窗口大致在变形温度20(lgε·+54)~1080℃,应变速率0.001~1 s^(-1)范围,该区域仅可发现少许动态再结晶晶粒,并有可能出现流动失稳现象。较佳变形参数窗口条件大致在变形温度1080~1160℃,应变速率0.018~1 s^(-1)范围,该区域可发生较充分的动态再结晶。最佳窗口条件大致为变形温度1080~1160℃,应变速率0.001~0.018 s^(-1)范围,该区域可获得完全动态再结晶组织。组织验证结果与加工图预测和优化结果吻合良好。
The hot deformation behavior of GH4742 superalloy at 950-1160℃and 0.001-1 s^(-1) was investigated based on the processing maps,and the dynamic response characteristic of power dissipation efficiency and instability parameters to the deformation thermomechani-cal parameters was analyzed.The power dissipation maps and the instability maps based on dynamic material model were constructed,and the processing maps of the alloy at different strains were obtained.The results show that the power dissipation efficiency and instability pa-rameters of the alloy are sensitive to the deformation thermomechanical parameters.The power dissipation efficiency increases with the de-crease of strain rate and the increase of deformation temperature.The instability parameters are generally smaller at high strain rates and low temperatures.The window of the instability parameters determined by the processing maps is about 950-20(lgε·+54)℃,0.001-1 s^(-1),and the corresponding main instability phenomena are adiabatic shear and flow localization.The window of the transitional micro-structure parameters is about 20(lgε·+54)-1080℃,0.001-1 s^(-1),where only a few dynamically recrystallization grains can be found in this zone and flow instability possible appears.The better thermomechanical parameters window is about 1080-1160℃,0.018-0.1 s^(-1),where relatively fully dynamic recrystallization behavior can occur in this zone.The optimum parameters window is about 1080-1160℃,0.001-0.018 s^(-1),where fully dynamic recrystallization microstructure can be obtained in this zone.The results of microstructure verifica-tion are in good agreement with those of processing maps prediction and optimization.
作者
冯彦成
王松辉
黎汝栋
徐东
苏海
葛金锋
罗通
FENG Yan-cheng;WANG Song-hui;LI Ru-dong;XU Dong;SU Hai;GE Jin-feng;LUO Tong(Guizhou Anda Aviation Forging Co.,Ltd.,Anshun 561005,China;Guizhou Academy of Sciences,Guiyang 550001,China;Institute of Metal Research,Chinese Academy of Science,Shenyang 110016,China)
出处
《塑性工程学报》
CAS
CSCD
北大核心
2024年第12期133-143,共11页
Journal of Plasticity Engineering
基金
国家重点研发计划(2022YFB3706904)
国家科技重大专项(2024ZD0600100)
贵州省高层次创新型人才项目(GCC[2023]098)
贵州省科技计划项目(ZZSG[2024]016)
安顺市科技计划项目(安市科工[2023]1号)。
关键词
GH4742高温合金
热变形行为
加工图
变形热力参数优化
GH4742 superalloy
hot deformation behavior
processing map
thermomechanical parameters optimization
