Study On Tool Wear In High-speed Turning 300m Steel With Cryogenic Minimum Quantity Of Lubricant

In green manufacturing process,cryogenic minimum quantity lubrication technology(CMQL)is an environmentally friendly,safe and green cutting technology,which combines cryogenic air technology(CA)and minimum quantity lubrication technology(MQL).It effectively combines the advantages of both and improves the shortcomings of their separate applications.After mixing cryogenic gas and lubricant droplets,the process can atomize these mixtures into micronsized particles in high-pressure and high-speed air convection to act on the cutting area.It can effectually reduce cutting force,reduce cutting temperature,reduce tool wear and improve the machining accuracy of the workpiece.Especially for machine materials of processing difficult,the advantage of cryogenic minimum quantity lubrication technology is more significant.As one of the typical aerospace difficult-to-machine materials,300 M steel has poor machinability because of its mechanical properties.It is embodied in the high cutting temperature at the cutting edge,uneven distribution of cutting force in the cutting area and large cutting force.When tool wear is serious,it can not be cutting because of the vibration.Many factors restrict the application and development of 300 M steel in this field.In this paper,the tool wear of high speed turning 300 M steel under cryogenic minimum quantity lubrication is studied based on experiments and finite element simulation.Firstly,the single factor experiments of high speed turning 300 M steel under cryogenic minimum quantity lubrication are carried out by using different coated cemented carbide tools to optimize the tool coating material.The tool radius is optimized by comparing different tool tip arc radius and the tool negative chamfering angle parameters are optimized by finite element software.Secondly,the optimum process parameters of cryogenic minimum quantity lubrication technology are selected.The influence of process parameters on tool wear and cutting force is judged by orthogonal test and range analysis.The empirical model of tool wear and cutting force is established.Model significance is tested.Thirdly,the orthogonal experiment of tool wear in high speed turning 300 M steel is carried out by using the optimum process parameters of cryogenic minimum quantity lubrication technology.The relationship between cutting parameters and tool wear is studied.The mechanism of tool wear is analyzed.Compared with dry cutting,the advantages of cryogenic minimum quantity lubrication technology in cutting process are analyzed.Finally,based on the orthogonal experimental data of tool wear,a tool flank wear prediction model is established with empirical formula.The significance test is carried out.The genetic algorithm is used to optimize the cutting parameters by minimizing tool wear,which providing theoretical guidance for actual production and processing.