The Cutting Property Of Natural Marble On HCM With CVD Coated Tools

High speed machining technology has the advantage of low cost,high efficiency and high machining accuracy,and is widely used in the automotive industry?mold manufacturing? instruments and meters,etc.So far,the application of high speed machining technology for metal materials is relatively mature,but its application for hard brittle material can't meet the requirement very well.Therefore,the problem that how to apply the high speed machining technology for hard brittle materials maturely has been solved.In this thesis,the variations of surface roughness,tool wear,cutting force,chip removal mechanism and surface topography were studied deeply during the high speed process applying CVD coating cutting tools to mill the white marble,which provide some theoretical basis for the application of high speed machining technology on the hard and brittle materials.During the orthogonal experiment of cutting force,the cutting force signal in stable phase was observed,due to air cutting,cutting force signal varied between "wave troughs and wave crests".The orthogonal experiment result showed the cutting force decreased with the increase of cutting speed,and cutting force increased with the increase of feed speed and cutting depth.The empirical formula showed that cutting depth was the most significant factor affecting the cutting force,the cutting speed was secondary factor,feed speed contributed little to cutting force.During the orthogonal experiment of tool wear,Zeiss microscope was used to observe wear morphology of the CVD coating tool,and the observation results showed that main wear patterns of the CVD coating tools included: flank wear?disbonding?exfoliate and collapse edge and build-up edge,etc,the flank wear and build-up edge are the main wear morphology for CVD coating tools in a low cutting speed;the main wear morphologies of the cutting tool are disbanding and collapse edge in a relatively high cutting speed.etc.The main wear reasons of CVD coating tools in the process of natural marble were summarized.The numerical analysis software SPSS was used to organize and calculate the wear data and establish the relation between wear amount of tools and cutting speed,feed speed,cutting depth.By cutting experiment,The removal way for marble material included large-scale cracked and small-scale cracked,Hitachi scanning electron microscope was used to observe the processed marble surface morphology,some pits,furrow,tool marks and other defect were found,and the damage was different for different process parameters.The roughness orthogonal experiment results showed that the marble surface roughness increased with the decresing of cutting speed,and the increased with the increasing of feed speed and cutting depth.