超高W含量NiW中/重合金热加工行为研究
Hot Workability of NiW Medium/Heavy Alloys with Ultra-high W Content
曹国鑫 1董建新 2张胜 3姚志浩 2解国良 2聂志华 4马腾飞 5付宝全3
作者信息
- 1. 北京科技大学材料科学与工程学院,北京 100083;西安聚能高温合金材料科技有限公司,陕西西安 710299
- 2. 北京科技大学材料科学与工程学院,北京 100083
- 3. 西安聚能高温合金材料科技有限公司,陕西西安 710299
- 4. 北京理工大学材料学院,北京 100081
- 5. 衢州学院浙江省空气动力装备技术重点实验室,浙江衢州 324000
- 折叠
摘要
采用Gleeble-1500D研究了 Ni-42W-10Co-1Mo(质量分数,％)中/重合金(MHA)在1150～1300 ℃和应变速率0.001～1 s-1下流变行为和微观组织演化规律.结果表明,该合金初始组织由面心立方基体和初生σ相构成.流变应力对变形温度和应变速率敏感,在较高应变速率1s-1下,应力-应变曲线呈现出典型的动态回复软化特征,而在较低应变速率0.1～0.001 s-1下变形应力-应变曲线呈现出典型动态再结晶软化特征.基于应力-应变曲线建立了 Arrhenius本构方程,并计算得到Ni-42W-10Co-1Mo合金热变形激活能为446.2 kJ/mol.基于动态材料模型构建该合金热加工图,发现在1300 ℃高应变速率下存在失稳区.通过微观组织分析,揭示其动态再结晶机制主要为不连续动态再结晶,σ相促进动态再结晶优先在其周围形核.最终优化获得了 Ni-42W-10Co-1Mo合金最佳的热加工窗口:1250～1300 ℃,应变速率0.1～0.01 s1.
Abstract
The flow behavior and microstructural evolution of a high-density Ni-42W-10Co-1Mo(wt％)alloy were investigated at 1150-1300 ℃ under strain rates of 0.001-1 s-1 using a Gleeble-1500D.The results show that the initial microstructure is composed of face-centered cubic matrix and σ phase.The flow stress is sensitive to the deformation temperature and strain rate,and the stress-strain curve shows typical dynamic revertive softening characteristics when deformed at 1 s-1,while typical dynamic recrystallization softening characteristics are observed when deformed at 0.1-0.001 s-1.The Arrhenius equation was established based on the stress-strain curves,and the hot deformation activation energy of the Ni-42W-10Co-1Mo alloy was calculated to be 446.2 kJ/mol.The thermal processing map was constructed based on the dynamic material model to evaluate the thermal processing performance,and the instable zone was located at 1300 ℃ under high strain rate.The deformation microstructural evolution reveals that the dynamic recrystallization mechanism is discontinuous dynamic recrystallization,which preferentially nucleates around the σ phase.Finally,the optimized hot working window for Ni-42W-10Co-1Mo alloy was obtained at 1250-1300 ℃ under strain rate of 0.1-0.01 s-1.
关键词
中重合金/镍基合金/热加工/本构关系Key words
MHA/nickel-based alloy/thermal processing/constitutive relationship引用本文复制引用
出版年
2024
NETL
NSTL
万方数据