DP处理高铌GH4169合金的热变形行为  

Hot Deformation Behavior ofδProcessed GH4169 Alloy with High Nb Content

作　　者：李宇力 周宣 马腾飞 张于胜[1,2] 张平祥 Li Yuli;Zhou Xuan;Ma Tengfei;Zhang Yusheng;Zhang Pingxiang(Northwest Institute for Nonferrous Metal Research,Xi’an 710016,China;Xi’an Rare Metal Materials Institute Co.,Ltd,Xi’an 710016,China)

机构地区：[1]西北有色金属研究院,陕西西安710016 [2]西安稀有金属材料研究院有限公司,陕西西安710016

出　　处：《稀有金属材料与工程》2020年第7期2470-2475,共6页Rare Metal Materials and Engineering

基　　金：陕西省博士后科学基金(2018BSHQYXMZZ38);中国博士后科学基金(2017M623333XB,2018M643760);陕西省自然科学基础研究计划(2019JQ-169,2019JQ-406)。

摘　　要：研究了经δ相时效处理(Delta Processing,DP)后的优质GH4169高温合金在不同变形温度(980、1010、1040、1070℃)及应变速率(0.001、0.01、0.1、1s^-1)进行热模拟压缩实验。结果表明:GH4169镍基高温合金在该变形条件下的平均激活能Q=528.24 kJ/mol,Nb元素含量上调会显著增加合金的变形激活能(约40 kJ/mol),该材料的热变形过程可通过双曲正弦本构模型进行描述。通过表征相应热变形后的显微组织,并结合GH4169高温合金的热加工图,表明GH4169高温合金适宜在低温低应变速率和高温高应变速率下加工。The high-quality GH4169 nickel-base superalloy has higher Nb content,and its microstructure is more sensitive to the process parameters,especially afterδphase aging(Delta Processing,DP)treatment;thus it is necessary to study its hot deformation behavior.In this paper,the hot deformation behavior of GH4169 alloy was studied by isothermal compression tests at the temperatures of 980~1070℃and strain rates of 0.001~1 s^-1.The results show that the deformation temperature and the strain rate have obvious effects on the flow characteristic.A constitutive model was established based on sine-hyperbolic Arrhenius kinetic rate equation,the value of average activation energy(528.24 kJ/mol)of GH4169 alloy is obtained,and increasing of Nb content will increase the modified activation energy significantly.Hot workability is interpreted by processing maps.The optimum hot working conditions for GH4169 ally is low temperature with low strain rate and high temperature with high strain rate area.

关 键 词：GH4169高温合金 热变形 动态模型 流变应力方程 热加工图 

分 类 号：TG146.416[一般工业技术—材料科学与工程] TG156.92[金属学及工艺—金属材料]