Experimental and modelling methodologies for fatigue crack nucleation around non-metallic inclusions in polycrystalline Ni-base superalloy.

粉末冶金已成为生产镍-高温合金涡轮机盘的首选方法。粉末冶金的一个不可避免的副作用是倾向于在镍基体中包含非金属团聚体。这些夹杂物可产生可驱动裂纹成核的局部活动应力场。最近的研究已经调查了不同的标准，在室温下的裂纹形核。喷气发动机涡轮机的真实的工作条件是在高温下，并且在这样的环境中裂纹成核的工作仍有待完成。该项目旨在通过使用实验和模拟技术来研究受高温条件影响的夹杂物周围出现裂纹的标准。

Powder metallurgy has become the preferred method for producing nickel-superalloy turbine disks. An unavoidable side-effect of powder metallurgy is the propensity to include non-metallic agglomerates in the nickel matrix. These inclusions may create a locally active stress field that may drive the nucleation of cracks. Recent studies have investigated different criteria for crack nucleation at room temperature. The real working conditions of a jet engine turbine are at high temperature and work remains to be done on crack nucleation in such an environment. This project aims to investigate the criteria for which cracks appear around an inclusion subject to high-temperature conditions by using experimental and modelling techniques.