摘要
通过热压缩实验、组织分析同时结合热力学和动力学计算方法,对700℃超超临界锅炉材料GH4700镍基合金组织演变进行研究,结果表明:GH4700镍基合金具有较高的变形温度和应变速率敏感性,随着变形温度的下降和应变速率的增大,合金的流变应力迅速升高,其动态再结晶形核方式为典型的应变诱导晶界迁移形核;其热变形激活能及晶粒长大激活能分别为345.0948kJ/mol和252.05kJ/mol。
By thermal compression experiment, microstructure analysis, combined with thermodynam- ic and kinetic calculation methods, the microstructure evolution of GH4700 superalloy for 700℃ ultra- supercritical boilers was studied. The results show that the GH4700 superalloy is more sensitive to the deformation temperature and strain rate. As the deformation temperature decreases and the strain rate increases, the flow stress of the superalloy increases rapidly. The mode of its dynamic recrystallization nucleation is a typical strain-induced grain boundary migration nucleation. The hot deformation activa- tion energy and grain growth activation energy are 345. 0948kJ/mol and 252.05kJ/mol respectively.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2013年第9期44-47,共4页
Journal of Materials Engineering
基金
国家"973"计划(2012CB723905)
山西省基础研究计划项目(2012011021-5)
关键词
超超临界
镍基合金
热变形
ultra-supercritical
Ni-base superalloy
hot deformation