一种Ni-Mo系高温合金的热变形行为及其组织演变  

Hot Deformation Behaviour and Microstructural Evolution of Ni-Mo Superalloy

作　　者：罗锐[1,4] 盛冬华 王资兴 高佩 陈乐利 徐昊翔 曹甫洋 Luo Rui;Sheng Donghua;Wang Zixing;Gao Pei;Chen Leli;Xu Haoxiang;Cao Fuyang(School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013,China;Institute of Novel Metals and Applied Technologies,Jiangsu Industrial Technology Research Institute,Changshu 215506,China;Jiangsu Yinhuan Precision Steel Pipe Co.,Ltd,Yixing 214203,China;State Key Laboratory of Mechanical Transmission for Advanced Equipment,Chongqing University,Chongqing 400044,China)

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013 [2]江苏省产业技术研究院先进金属材料及应用技术研究所,江苏常熟215506 [3]江苏银环精密钢管有限公司,江苏宜兴214203 [4]重庆大学高端装备机械传动全国重点实验室,重庆400044

出　　处：《稀有金属材料与工程》2024年第11期3111-3120,共10页Rare Metal Materials and Engineering

基　　金：重庆大学高端装备机械传动全国重点实验室(SKLMT-MSKFKT-202219);江苏省自然科学基金(BK20220548);新金属材料国家重点实验室(2022-Z21);江苏省先进结构材料与应用技术重点实验室开放基金(ASMA202203)。

摘　　要：利用先进的Gleeble热模拟技术和电子背散射衍射(EBSD)等表征手段研究了一种Ni-Mo系高温合金(Hastelloy B3合金)在变形温度950~1250℃、变形速率0.01~5 s-1条件下的热变形行为和微观组织演变。基于峰值应力构建了该合金的Arrhenius双曲-正弦本构模型。根据加工硬化率-应变量曲线确定Hastelloy B3合金的动态再结晶(DRX)临界应变,并基于Avrami方程建立其DRX体积分数模型。结果表明:DRX行为倾向于高温和低速率的变形参数下发生。通过EBSD对该合金变形组织的晶界角度和位错密度进行分析可知,位错易在原始晶粒边界处聚集形成小角度晶界进而演变为大角度晶界,因而Hastelloy B3合金的主要DRX机制被确定为不连续动态再结晶(discontinuous dynamic recrystallization,DDRX)为主,连续动态再结晶(continuous dynamic recrystallization,CDRX)为辅。The hot deformation behaviour and microstructural evolution of a kind of Ni-Mo alloy(Hastelloy B3)were investigated by Gleeble-3500 thermal simulation tester in the temperature range of 950-1250℃,and in the strain rate range of 0.01-5 s-1.Electron backscatter diffraction(EBSD)was used to analyze the microstructure evolution.Arrhenius constitutive model of this alloy was developed on the basis of peak stresses.The microstructural evolution of Hastelloy B3 alloy during deformation was observed via an optical microscope.The critical strain of dynamic recrystallization(DRX)of Hastelloy B3 was identified based on the work hardening rate versus flow stress curves.The DRX kinetics for Hastelloy B3 alloy can be represented in the form of Avrami equation.The results show that DRX behaviour tends to occur at high temperatures and low strain rates of deformation parameters.According to the EBSD analysis of the grain boundary angle and dislocation density of the deformed organisation of the alloy,dislocations tend to accumulate at the original grain boundaries to form low-angle grain boundaries and then evolve into high-angle grain boundaries.Thus,the main DRX mechanism for Hastelloy B3 alloy is identified to be discontinuous dynamic recrystallisation(DDRX)with continuous dynamic recrystallisation(CDRX)as a supplement.

关 键 词：Hastelloy B3 动态再结晶 本构方程 临界应变 再结晶动力学 

分 类 号：TG1132.33[金属学及工艺—物理冶金]