(1. 西安建筑科技大学 冶金工程学院,西安 710055;
2. 金川集团股份有限公司,镍钴资源综合利用国家重点实验室,金昌 737100;
3. 功能材料加工国家地方联合工程研究中心,西安 710055)
摘 要: 利用Gleeble-3500热模拟试验机对真空感应(VIM)+电渣重熔(ESR)所得的GH5605合金铸锭进行热压缩实验,研究其在变形温度为 950~1200 ℃、应变速率为0.001~10 s-1、真应变为0.65时的热变形行为。结果表明:铸态GH5605合金的真应力-应变曲线属于加工硬化+动态回复型,分为3个阶段,即Ⅰ剧烈加工硬化阶段、Ⅱ平缓加工硬化阶段、Ⅲ稳态流变阶段。建立的Arrhenius本构方程相关系数(Rr)和平均相对误差(δ)分别为0.95和11.99%,结合热加工图和变形组织分析得出GH5605合金良好的加工区域为变形温度1055~1200 ℃、应变速率0.01~0.1 s-1。
关键字: 钴基高温合金;热变形行为;本构模型;热加工图;显微组织
(1. College of Metallurgy Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China;
2. State Key Laboratory of Nickel and Cobalt Resource integrated utilization, Jinchuan Group Co., Ltd., Jinchang 737100, China;
3. National & Local Engineering Researching Center for Functional Materials Processing, Xi’an 710055, China)
Abstract:Hot compression deformation tests of cobalt base superalloy 5605 alloy by vacuum induction electroslag remelting were performed on Gleeble-3500 thermal simulator. The deformation behavior of as-cast GH5605 alloy was studied at the temperature ranging from 950-1200 ℃, strain rate ranging from 0.001 to 10 s-1 with true strain of 0.65. The results show that the true stress-strain curve of GH5605 alloy belongs to the working hardening type + dynamic recovery type. The true stress-strain curve of GH5605 alloy is mainly divided into three stages: Ⅰ severe work hardening stage; Ⅱ gentle work hardening stage; Ⅲ steady stage. The average relative error (δ) of the constitutive model is 11.99%, the correlation coefficients (Rr) is 0.95, the optimum hot working domain for GH5605 alloy is 1055-1200 ℃ and 0.01-0.1s-1.
Key words: cobalt-based superalloy; hot compression deformation; constitutive modeling; processing map; microstructure