Experimental Investigation On Cold Air Cutting Technology In Green Machining

In metal cutting, the extensive use of cutting fluid oil causes serious harm to environment and operators, therefore, a growing number of restrictions has been made for its using, which makes the green cutting technology become the new trend of development of metal processing. In this paper, a systematic experimental study was taken about cold air micro-lubrication cutting technology applications in machining based on the status and characteristics analysis of green cutting technology at home and abroadIn this paper, cold dry air(0-60℃) obtained by artificial refrigeration was sprayed to cutting area, and in this way Experimental researches were done in the process of turning and hobbing. To explore the mechanism of the low-temperature cold air cooling lubrication, the combining method of numerical calculation and experimental research was used, and characteristics and mechanism of low-temperature cold air cutting process in enhancing the performance of cooling lubrication and the quality of workpiece surface were analyzed. And we obtain the following results:Firstly, the tool temperature field was analyzed and obtained by numerical analysis under low-temperature cold air cutting. relationship between effect of cold air and temperature and pressure of the cold air was analyzed, and validated test was done.Secondly, though the comparing experimental study between the cold air micro-lubrication cutting and room temperature dry cutting, we can confirm that cold air micro-lubrication cutting can reduce the surface plastic nature and cutting temperature, thereby reducing the tool rake face and flank wear, increase tool life; In the same time , cold air jet can effectively inhibit the machined surface of the BUE and the scales of thorns, and bring down the surface roughness and improve cutting quality;Finally, Selection experiment of for gear hobbing 45 # steel under cold air micro-lubrication cutting environment was done. The orthogonal method was be used to find out the optimal process parameters and the significant degree of factors to the tooth surface roughness. The results showed that cold air micro-lubrication cutting can be more effective in reducing the cutting zone temperature, tool wear and tooth surface roughness compared to conventional oil cutting. And the optimal process parameters were: cold air temperature of -45℃, feed-rate of 0.2mm/r, micro-lubrication quantity of 40ml / h. All test results have shown that cold air micro-lubricant has a very active role in the inhibition of tool wear and improvement surface quality. Because micro-lubricant has strong penetration and adsorption capacity under high speed cold air,which can quickly form lubricating film in the fresh surface between tool-chip and tool-work-piece, and inhibits the production of cutting heatCold air micro-lubrication cutting in machining ,as a preferable alternative to conventional flood lubricating system , can effectively reduce the cutting temperature, tool wear and improve surface quality, has great development prospects.