Effect Of 45~# Steel Milling Process Parameters On Residual Stress Of Machining Surface

Nowadays,with the rapid development of manufacturing industry,there are more and more types of spare parts.Among them,45~#steel special-shaped parts are widely used in many industries.Because of their unique function,they are difficult to be replaced by other parts.At present,the machining of special-shaped parts is mainly processed by milling.During the milling process,due to the interaction of various factors,the workpiece surface will inevitably generate residual stress,which will affect the accuracy,durability and fatigue strength of parts.Therefore,the paper will apply the method of theoretical analysis,simulation and experiment to study the residual stress in the surface of 45~#steel.This paper is expected to play a guiding role in the milling of 45~#steel,so as to reduce the adverse effects of surface residual stress on the parts and improve the quality of the special-shaped parts.Main research contents and results:(1)This paper first studies the formation process of the residual stress on the surface of the workpiece in the cutting process.The cause of the residual stress caused by the mechanical and thermal stresses is analyzed.On this basis,the effect of thermo-force coupling on the surface residual stress of workpiece is studied.(2)A two-dimensional orthogonal finite element simulation model of milling 45~#steel was established by ABAQUS software.According to the simulation results,the influence of each cutting parameter on cutting temperature,cutting force and residual stress is analyzed in detail.The results show that the residual stress on the surface of the workpiece is compressive stress.When the cutting speed increases,the cutting force and the surface residual compressive stress all decrease.When the feed per tooth increases,the cutting force and surface residual compressive stress increase correspondingly.The cutting temperature increases with the increase of cutting speed and feed per tooth,and the extent of increase decreases.(3)The milling experiment of 45~#steel is carried out.Firstly,the influence rule of cutting depth on residual stress is studied.The research shows that the influence of cutting depth on residual stress is less.Secondly,the simulation model and the results are verified.The results show that the maximum error of the simulation and experimental results is 14.3%,which shows that the simulation model is accurate and the simulation results are reliable.The residual stress of the workpiece surface can be studied by simulation model instead of experiment.(4)According to the orthogonal test results,the residual stress of the workpiece surface is the output with the cutting parameters as the input,and the BP neural network structure model is used to predict the residual stress values of the machined45~#steel surface.The prediction results are basically consistent with the experimental results;The residual stress on the surface of workpiece is analyzed by range anal ysis.The results show that the optimum cutting parameter combination for milling 45~#steel is 45m/min,the feed per tooth is 0.2mm/r,and the cutting depth is 0.4mm.