高温合金磨削热损伤的形成机理及对表面完整性的影响OA北大核心CSTPCD

Thermal damage defects are prone to occur during the grinding process of superalloys,which seriously reduces the fatigue life of parts.To address this engineering issue,this paper uses zirconium corundum grinding wheels and microcrystalline corundum grinding wheels to carry out creep-deep grinding experiments on superalloys.The effects of grinding process parameters on grinding temperature,grinding force,surface morphology,and surface roughness were studied.The formation mechanisms and effective suppression measures of thermal damage in superalloy grinding were revealed.The influence of grinding thermal damages on surface integrity was compared and analyzed.The results indicate that the instantaneous high temperature in the processing arc zone is the essential cause of the thermal damage of superalloy grinding.Microcrystalline corundum grinder can suppress grinding thermal damages productively due to its self-sharpening advantage.The surface of superalloy alloy grinding with thermal damages exhibits oxidation discoloration,fish scale-like coating texture,decreased hardness,and residual tensile stress.An effective means to realize the thermal damage-free grinding of superalloys is to reduce the generation of grinding heat and strengthen the heat transfer in the machining arc region.