Research On Wear Of PCD Tools Dry Cutting Copper Alloy Based On Green Processing

PCD tools can obtain high machining accurancy and efficiency in high-speed cutting because of their high hardness,good wear resistance,low thermal expansion coefficient and low friction coefficient.It is widely applied in many fields,such as aerospace,automobile and so on.Dry cutting technology is a new green manufacturing technology at present and it fundamentally eliminates the negative effects of traditional maching technique polluting the environment and endangering workers’ health without using cutting fluid.Therefore the combination of the high-speed cutting technology and the dry cutting technology of PCD tools will be an important direction for the future development of cutting processing technology.However,dry cutting will inevitably increase the cutting temperature and force because of the lack of cutting fluid,which leads to the increase of cutting tool wear and the reduction of machining efficiency,and it is unfavorable to the application of PCD tool in dry cutting.Based on this,Two different types of PCD cutting tools were used for high-speed dry cutting test of tin lead copper alloy CuSn7Pb15-C.The tool wear process and machining ability were compared and analyzed.The effect of tool material on wear and the feasibility of the dry cutting of PCD tool in the actual production were studied.The difference of wear morphology and wear mechanism of cutting tool of two types under different conditions were explored.First,two kinds of PCD cutters of CTB010 and CMX850 were used in dry cutting finishing experiments.The wear process of the tool were compared and analyzed.The effect of tool material on tool wear was studied.The results showed that the wear degree of the two kinds of cutting tools increased slowly with the increase of the number of cutting parts.However,the wear rate of CTB010 tool is faster than that of CMX850.After the same number of workpiece was processed,the CTB010 tools reached the grinding blunt standard earlier than CMX850.Compared with the processing efficiency of the two tools,the advantages of CMX850 tools are obvious,which can be popularized and applied in the production practice.The reason cutting performance of CMX850 tool is better than that of CTB010 tool is because the performance of the tool material is superior in the former tool,which improves the bond strength and stability of the tool,and shows better high temperature resistance and stronger bond resistance in dry cutting.On the other side,the former size of the diamond particles is smaller and the cutting edge of the tool is sharper.It is not easy to cause large gaps after been worn,so the cutting performance and machining quality of CMX850 tools are superior to those of CTB010.Secondly,the wear morphology of two types of PCD cutters after processing was observed by stereoscopic microscope and scanning electron microscope.The results showed that the wear form of CTB010 mainly manifested as flaking and slight breakage,and CMX850 was mainly characterized by micro-chipping.In addition,in the process of cutting,the two kinds of cutting tools have different degrees of brittle breakage,which are characterized mainly by the chipping,the overall fracture of the cutting edge,and the large area flaking of the rake and rear surface of the tools.At last,the chemical composition of tool wear area was analyzed by X ray spectrometer.The results showed that the tool wear was caused by many factors such as heat and chemical change during the process of high speed dry cutting.The main cause of the wear is diffusion,oxidation and bond wear under the effect of high temperature.The oxidation wear is mainly caused by the oxidation reaction of C and Co in diamond cutting tools,which reduce the tool strength,and the diffusion wear is mainly caused by the mutual diffusion between workpiece materials and tool material elements,which weakens the cutting performance of cutting tools.