关键词: FGH96, 拉削, 表面粗糙度, 残余应力, 表面形貌, 维氏硬度

Abstract: FGH96 is a powder metallurgy material widely used in high-temperature environments. As a machining method for key features such as FGH96 turbine disk tongue and groove,the selection of broaching process parameters directly affects the serviceability and life of the final part. The surface integrity of broached FGH96 material is investigated,and the effects of different process parameters on surface roughness,surface morphology,residual stress and microhardness are analyzed. The result shows that surface roughness is reduced with the increase of the front angle,and is increased with the increase of tooth rise and broaching speed;surface morphology is improved with the increase of the front angle,and is deteriorated rapidly with the increase of the tooth rise and the speed;the residual stress on the surface in the direction of broaching is manifested as compressive stress,and in the direction of perpendicular broaching,it is manifested as tensile stress;the Vickers hardness on the surface is reduced with the increase of the front angle of the broach and the increase of the speed,and is reduced with the increase of tooth rise. In-depth understanding and study of the FGH96 broaching surface integrity is of vital significance for improving the fatigue resistance,reliability and safety in extreme environments of key components such as turbine disks.

Key words: FGH96, broaching, surface roughness, residual stress, surface morphology, Vickers hardness