Trial Research On Micro-textured Ultrahard Tool Cutting Valve Seat

Reasonable micro-texture can reduce the force of the tool-chip interface.In this dissertation,Turning powder metallurgy valve seat with micro-textured ultrahard PCBN tool is used to discuss the effects of cutting speed and texture parameters on cutting force,cutting temperature and roughness of machined surface.The main research contents are as follows:(1)The experiment designs the circular dimple-array micro-texture and processes micro-texture on the rake face by laser processing.Machining quality of the micro-texture is detected by laser microscope system of shape measurement.The reasonable geometrical parameters of micro-texture tool are obtained by tool sharpener.(2)The cutting temperature was measured under dry cutting condition.Experimental results show that the order of significant influence of various factors on cutting temperature is dimple density w > cutting speed v > dimple depth h > dimple diameter d.When v = 90m/min,the temperature measurement results of groups 06,07 and 08 are lower than that of the non-textured tool group w2.The effect of micro-texture on cutting temperature is not significant.(3)The cutting force and surface roughness was measured under dry cutting condition.Experimental results show that the order of significant influence of various factors on cutting force is d > h > v > w.Compared with non-textured tool,the reasonable surface micro-texture can reduce the cutting force.The order of significant influence of various factors on surface roughness is v > w > h > d.The effect of micro-texture on surface roughness is not significant.(4)Pour cutting fluid and conduct cutting tests with the same cutting parameters.Experimental results show that d is the most significant factor affecting cutting force.At each cutting speed,the cutting force of the texture tool is less than that of the non-texture tool.The effect of v on surface roughness is much greater than that of texture parameters.The effect of micro-texture on workpiece surface roughness is not significant also.The completion of this dissertation enriches the application of micro-textured tools.it has theoretical and practical significance for the application of micro-textured tools in the cutting of powder metallurgy valve seat materials.