镍基单晶高温合金定向粗化机制有限元分析

采用有限元计算了[001]取向时,镍基单晶合金中γ基体和γ′沉淀相在施加外力前后弹性应变能密度的分布,并依据元素的扩散性质对定向粗化过程做了相应分析.结果表明,外应力改变了基体通道中的应变能密度的分布,γ′沉淀颗粒的定向粗化与基体通道中的应变能密度分布密切相关,其定向粗化在应变能密度高的基体通道扩展,且应变能密度变化越大,元素扩散速率越快,γ′颗粒定向粗化的速率也越快.

Finite Element Analysis of Directional Coarsening Mechanism in Ni-Based Superalloys

Finite element analysis is applied to calculate the elastic strain energy density distribution in the gamma matrix and gamma' precipitate along the orientation before and after loading,and the analysis of directional coarsening process is performed based on the element diffusion behavior.The results indicate that the strain energy density distribution of matrix channel has been changed by the application of the external stress.The directional coarsening of gamma' precipitate is closely related with the strain energy density distribution in the matrix channels,and the directional growth of gamma' precipitate is in the most highly strain energy density matrix channels;The rate of gamma' precipitate directional coarsening and element diffusion accelerate with the increase of the strain energy density.