摘要
用晶体热粘塑性模型研究了镍基合金中γ与γ′相的非弹性行为,进行了在晶体塑性理论基础上考虑镍基高温合金中的随机分布相结构对其蠕变与损伤过程的数值模拟.模拟假定合金中γ′相的尺寸及分布具有随机性,γ与γ′相在高温下的变形、损伤用温度相关的晶体粘塑性损伤本构关系进行计算,计算结果与周期体胞模型进行了比较.结果表明:γ′相随机分布模型能够反映镍基合金微观变形和应力分布不均匀、局部剪切变形和可能的破坏倾向;该模型的蠕变分析结果较周期体胞模型合理.
The microscopic evolution of creep and damage of a nickel base superalloy under elevated temperature tension was analyzed by assuming that the size and distribution of γ＇ phase in alloy are random. The deformations and damages of γ-matrix phase and γ＇ precipitate phase under high temperature were calculated by using temperature dependent crystal viscoplastic damage constitutive relation. The calculated results show that the random distribution model of γ＇ phase can describe non-uniformed microstructure deformation, stress distribution and local shearing band, and can predict the different possible damages in nickel base alloy. The results were compared with those calculated by simplifying period cell model without considering the randomness for the γ＇ precipitates, which indicated the random distribution model is more reasonable than the simplifying period cell model.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第9期961-967,共7页
Acta Metallurgica Sinica
基金
国家自然科学基金项目10472092和10662001
航空科学基金项目04C53027资助
关键词
镍基两相合金
晶体塑性
随机构成模型
微观蠕变损伤
nickel base two-phase superalloy, crystalline plasticity, randomly aggregated model, microscopic creep and damage
