镍基粉末高温合金的热变形行为和微观组织演变  

Hot deformation behavior and microstructure evolution of nickel-based powder superalloys

作　　者：王强 张兵 瞿宗宏 雷智强 赖运金 李少强 王快社 WANG Qiang;ZHANG Bing;QU Zong-hong;LEI Zhi-qiang;LAI Yun-jin;LI Shao-qiang;WANG Kuai-she(National and Local Joint Engineering Research Center for Functional Materials Processing,School of Metallurgical Engineering,Xi′an University of Architecture and Technology,Xi′an 710055,China;Sino-Euro Materials Technologies of Xi′an Co.,Ltd.,Xi′an 710018,China)

机构地区：[1]西安建筑科技大学冶金工程学院功能材料加工国家地方联合工程研究中心,陕西西安710055 [2]西安欧中材料科技有限公司,陕西西安710018

出　　处：《塑性工程学报》2025年第3期208-218,共11页Journal of Plasticity Engineering

基　　金：陕西省重点研发计划(2022-LL-JBGS-00X);陕西省秦创原“科学家+工程师”队伍建设(2023KXJ-012)。

摘　　要：对固溶态镍基粉末高温合金进行了热压缩实验,研究了合金在1000~1200℃/0.001~1 s~(-1)变形条件下的热变形行为和组织演变。结果表明:随变形温度升高和应变速率降低,合金流变应力逐渐减小,真应力-真应变曲线分为动态回复和动态再结晶阶段。在1000~1100℃时,γ′相在γ基体中析出,其面积分数随变形温度和应变速率的升高逐渐减小,处于γ′+γ相区,初生γ′相钉扎晶界,抑制晶粒长大。这一温度区间内存在连续动态再结晶和不连续动态再结晶两种动态再结晶机制。在1150~1200℃,γ′相完全回溶至γ基体中,处于γ相区,晶粒尺寸随应变速率降低逐渐长大,再结晶机制主要为DDRX。根据Arrhenius本构关系建立了合金的本构方程,相关系数为0.9917,平均相对误差为9.91%,可以较为精确的预测流变应力。Hot compression tests were performed on the solid solution state nickel-based powder superalloys,and the hot deformation be-havior and microstructure evolution of the alloy were studied at deformation conditions of 1000-1200℃/0.001-1 s^(-1).The results show that the flow stress of the alloy gradually decreases with the increase of deformation temperature and the decrease of strain rate.The true stress-true strain curves are divided into dynamic recovery(DRV)and dynamic recrystallization(DRX)stages.At 1000-1100℃,the γ′phase precipitates in theγmatrix,and the area fraction decreases gradually with the increase of deformation temperature and strain rate,being located in the γ′+γphase region.The primary γ′phase pinnes the grain boundaries,inhibiting grain growth.Within this tem-perature range,two mechanisms of dynamic recrystallization(DRX)were present:continuous dynamic recrystallization(CDRX)and dis-continuous dynamic recrystallization(DDRX).At 1150-1200℃,the γ′phase completely dissolves back into theγmatrix,situated in theγphase region,and the grain size gradually increases as the strain rate decreases,with the main recrystallization mechanism being DDRX.Based on the Arrhenius constitutive relationship,a constitutive equation for the alloy was established,and the correlation coeffi-cient is 0.9917,the average relative error is 9.91%,allowing for a relatively accurate prediction of the flow stress.

关 键 词：镍基粉末高温合金 动态再结晶 γ′相 晶粒长大 本构关系 

分 类 号：TG146.11[一般工业技术—材料科学与工程]