Study On The Wear Mechanism Of AISI304 Stainless Steel Tool In High Speed Internally Cooled Milling

AISI304 stainless steel is widely used in aviation,shipping,medical and other high-tech fields because of its excellent comprehensive performance in high temperature corrosion environment,and has broad research space and application prospects.However,due to its low thermal conductivity and strong plasticity,it has the characteristics of large cutting force,hard to control the surface quality and serious work hardening in the process of cutting,which results in increased tool wear,reduced chip sticking and durability.In view of the above problems,the use of internally cooled milling is an effective way to improve the processing quality.Through the high-speed internally cooled milling test and finite element simulation analysis,the milling temperature and milling force change rule are analyzed,and the wear morphology of end milling cutter was observed to reveal the wear mechanism of high-speed internally cooled milling cutter,so as to provide an ideal scheme for improving the processing quality and efficiency.According to the experimental milling environment,the three-dimensional model of high-speed internally cooled milling is established,and the finite element analysis of AISI304 stainless steel is preceded,and the model is verified by experiments.The orthogonal experiment method is used to analyze the influence of different milling parameters on the milling temperature,and the milling temperature distribution of the main cutting edge is analyzed.The maximum temperature in the test is 396 ?,the maximum temperature through the simulation is 355 ?,and the trend of the simulation temperature is consistent with the test temperature.The impact on the milling temperature is that the speed > the feed per tooth > the milling depth.The maximum temperature in the cutting area appears near the tool tip,and the change trend of the temperature of the side edge is slower than that of the shear edge,thus the simulation results provide a basis for the wear of the milling tool surface.Through the test of milling force of AISI304 stainless steel in high-speed internally cooled milling,the single factor test and response surface center composite test are designed,and the influence rule of single factor and interaction factor on milling forcecomponent are analyzed intuitively.Based on response surface method,the prediction model of high-speed internally cooled milling force component is established,the precision and reliability of the prediction model are evaluated theoretically and experimentally,and the milling parameters are optimized.The effective levels of these factors successively are milling depth,speed,and feed rate.The interaction of milling depth and speed has a significant effect on feed force and radial force.The errors of predicted force and radial force are 4.77% and 6.16% respectively.Taking the minimum component of milling force as the optimization objective,a group of optimal milling parameters are obtained:rotational speed 11643.63 RPM,milling depth 1 mm,and feed rate 0.08mm/r.This paper analyzes the tool wear form of high-speed internal cooling milling and the milling force evolution in different milling environments,observes the wear morphology of cutting edge in high-speed internal cooling milling environment,and reveals the tool wear mechanism in this condition.The main wear forms of high-speed internally cooled milling tools are front and back face wear,cutting edge wear and tool tip wear.The mechanism of tool wear is very complex,due to mechanical wear,adhesive wear,diffusion wear and strong reactions.Because of the resultant force of various factors,the tool wear morphology is also cross symbiosis.Under the effect of cutting fluid,a layer of lubricating film is formed between the tool and the workpiece,which reduces the friction among the tool chips,restrains the adhesive wear,greatly reduces the tool wear and improves the service life of the tool.