摘要
Inclusion flaw is one of the worst flaws of powder metallurgy.The inclusion flaw plays an important role in the failure of high temperature turbine materials in aircraft components and automotive parts,especially fatigue failure.In this paper,an experimental investigation of fatigue microcrack propagation in the vicinal inclusion were carried out by the servo-hydraulic fatigue test system with scanning electron microscope(SEM).It has been found from the SEM images that the fatigue surface microcrack occurs in the matrix and inclusion.According to the SEM images,the characteristics of fatigue crack initiation and growth in vicinal inclusion for powder metallurgy alloys are analyzed in detail.The effect of the geometrical shape and material type of surface inclusions on the cracking is also discussed with the finite element method(FEM).
Inclusion flaw is one of the worst flaws of powder metallurgy.The inclusion flaw plays an important role in the failure of high temperature turbine materials in aircraft components and automotive parts,especially fatigue failure.In this paper,an experimental investigation of fatigue microcrack propagation in the vicinal inclusion were carried out by the servo-hydraulic fatigue test system with scanning electron microscope(SEM).It has been found from the SEM images that the fatigue surface microcrack occurs in the matrix and inclusion.According to the SEM images,the characteristics of fatigue crack initiation and growth in vicinal inclusion for powder metallurgy alloys are analyzed in detail.The effect of the geometrical shape and material type of surface inclusions on the cracking is also discussed with the finite element method(FEM).
