Preparation Of WS₂/Cr-AlCrSiN Soft-hard Coated Tool And Its Performance

Hard coating has a high hardness,which can effectively improve tool wear resistance,and it has been widely used in cutting field.However,it has a high friction coefficient,which limits the cutting performance.Especially in aviation manufacturing and biomedical material processing,cutting fluid is not allowed and high friction coefficient of tool leads to serious cohesive wear.Those facts will reduce tool life.In this paper,WS₂/Cr soft coatings were deposited on the surface of AlCrSiN coating tools by Radio Frequency Magnetron Sputtering and Multi-Air Ion Plating,and the WS₂/Cr-AlCrSiN soft-hard coated tools with both friction reduction and wear resistance were prepared.The characteristics and performance of tools are systematically studied.The contents are as follows:The effects of the preparation technology of WS₂/Cr composite soft layer were studied,the effect of deposition temperature and pressure,sputtering power on the hardness,adhesion,crystallinity and chemical composition of the coating were analyzed,and the optimum parameters of WS₂/Cr composite soft coatings were determined.The optimum result is the deposition temperature was 250°c,the sedimentary pressure is 0.5pa,WS₂ target power is 150W and the negative bias is-100V.The friction and wear characteristics of WS₂/Cr coatings with different Cr composition were systematically studied,and the variation of friction coefficient of coatings with wear time were compared and analyzed.The wear resistance of each group of coatings was compared by measuring the coating residue of friction plate and the wear rate of friction balls,and the results showed that when the Cr composition was about 9.8%?Cr target sputtering power is 55W?,the overall average friction coefficient of WS₂/Cr coating,the coating residue of friction plate and the wear rate of friction ball is the best.chip curl radius is the smallest,the chip is the easiest to break,and the tool temperature is the lowest according to the result the cutting simulation model.The cutting performance of WS₂/Cr-AlCrSiN soft-hard coated tool in titanium and aluminum alloy drilling was studied by comparing with the performance of tool with AlCrSiN and tool without coating.The results showed that the bit of coating WS₂/Cr-AlCrSiN coating can significantly reduce the bonding of chips,improve the fluency of chip removal,which lead to reduce bonding materials area,heat accumulation,which lead to reduce tool wear,improve tool life.