夹杂物在FGH95中的损伤力学行为研究

通过损伤力学的研究方法模拟平面拉伸应力作用下夹杂物及周围基体中的应力场分布情况,并通过原位拉伸试验对模拟结果进行验证。结果表明,在夹杂为圆形的情况下,当基体处于弹性状态时,极点处将有一定的拉应力集中,裂纹将从该处萌生;当基体处于弹塑性状态时,应力集中位置将转移到赤道面处,裂纹在该处向基体中扩展。在夹杂为方形的情况下,裂纹在极点处萌生,并在尖角应力集中处向基体中扩展。模拟结果与试验结果的对比说明,在模拟过程中将基体分为弹性和弹塑性两个阶段是可行的。

A Study of Damage Mechanical Behavior for Non-Metallic Inclusion in P/M FGH95 Superalloy

The distribution of stress field in non-metallic inclusion and matrix was simulated by the means of damage mechanical.And the simulation results were approved by in-situ tension experiment.The results show that tensile stress concentrates at the top of round inclusion from which the fracture initiates when the matrix is elastic,and then at the its equator from which the fracture propagates into the matrix while the matrix is elastic-tenacity;The fracture initiates at the top of the quadrate inclusion,and propagates into the matrix from its sharp corner.The simulation results are approved well by in-situ tension experiment,which indicates that the two stages,elastic-tenacity,should be used into the simulation.