The Study On Characterization Of Machined Surface Micro-Topography In High Speed Milling Of SiC_p /Al Composites

With the development of the aviation and automobile industry in recent years, the requirement for high performance material becomes urgent. The SiCp/Al composites are widely used for its high specific stiffness and high specific strength. But, the poor surface quality and cutting performance limit its further application. To investigate the assessment method and seek for the characterized method of machined surface micro topography are important for controlling the quality of machined surface.The experiments of high speed milling are done in this dissertation. The surface micro-topography was tested by the Taylor scan150 roughness tester and OLS 300 microscope. The Gaussian filtering method and the least square fitting method were also investigated. The Gaussian method was identified to process the original data through the comparison of the treated results. The treated results were used for three dimensional surface roughness.The theory of power spectral density was investigated and the program was finished by the Matlab software. The treated data was analyzed by the power spectral density. The effect laws of cutting parameters on power spectral density were obtained and explained by means of cutting process.Finally, the theory of three dimensional surface roughness was introduced due to the disadvantage of two dimensional surface roughness method. The physical and geometric meaning of the parameters was explained. The finished surfaces were characterized by the three-dimension surface roughness method. The effect laws of cutting parameters on three dimensional surface roughness were explain by means of cutting process. The results showed that the cutting speed is most important for the surface quality, then the feed rate, and the next is depth of cut.