Study On The Milling Performance Of Textured Ball-end Milling Cutter With Coating

A unique shaped cutter named ball-end milling cutter is often used when it comes to the mold cavity milling of aircraft and automobile covering parts and their key components.Owing to its Sshaped major cutting edge,the process of cutting in and out of the workpiece is smooth,the three components of the cutting force are relatively small,and the fluctuation range is narrow,which is fairly suitable for the finishing of various complicated curved surfaces and arc grooves.However,during milling aluminum alloys,ball-end milling cutters often suffer from severe thermal and mechanical effects,leading to the increasingly prominent wear of the rake and rear cutting surfaces near the major cutting edge,which directly affects the using life span of ball-end milling cutters and the surface quality of the machined parts.Aluminum alloy structural parts are being used in so large quantities in the manufacture of automotive and aircraft parts that milling quality of ballend milling cutters is directly related to their manufacturing accuracy and indirectly affects the development of our national heavy manufacturing economy.In order to solve this problem,people often use coating technology to deal with it,but in the daily practice,defects like coating peeling and cracking also frequently erupt,which should not be underestimated.In recent years,surface texturing technology has gradually entered people’s field of vision as a cutting-edge emerging one and has been recognized by scientific researchers.Studies have shown that by inserting the texture on the working surface of the tool,the cutting force can be effectively reduced,the friction status can be improved,the degree of wear can be reduced,and the bonding strength of the coating base can be enhanced and the residual stress inside coatings can be reduced.Therefore,this article will focus on the development of a new type of coating textured ball-end milling cutters,explore the feasibility of putting textures onto the ball-end milling cutters,explore the influence of laser processing parameters on the texture,and simulate ball-end milling cutters cutting aluminum alloys,and high-speed milling experiments were conducted to find out the milling performance of coated textured ball-end milling cutters.The main contents of this paper are as follows.Firstly,a systematic review of basic theories of the metal cutting is provided to give theoretical support and testimony for subsequent research work.The chip forming mechanism and its influencing factors are analyzed,and combined with the knife-chip contact model,the chip contact area is divided.According to the characteristics of the working conditions in each zone,the parameters,such as the location,type and area occupation rate of the texture layout are designed.Based on the coating formation and failure mechanism,the mechanical anchoring effect of the texture was predicted.In addition,the tool wear mechanism is analyzed,and the surface texture of the tool is proposed.Secondly,based on laser ablation and fusion,a texture processing strategy was developed,and the forming process method of MGT-type groove texture and VLT-type crater-like texture point texture was studied.With cemented carbide as the target,the effects of the pumping current and scanning speed of the picosecond laser on the width and depth of the grooves for the MGTtype groove texture were studied;for the VLT-type crater-like furring point,the laser power,the pulse width and the number of scans affect its diameter,depth,and protrusion height,and explain their forming principles.Thirdly,3D models of five ball-end milling cutters with different texture types and area occupancies were established in NX UG after selecting the optimal texture parameters,and they were imported into DEFORM professional cutting software to simulate milling aluminum along the arc path.In the process of alloy Al6061 sheet,the differences in milling temperature,milling force and wear amount are compared and studied.The research results show that compared with the untextured coated ball cutter NT,the MGT ball cutter with an area share of 30% has the most significant cooling effect under dry cutting conditions,reaching 9.56%;the area share is The 30% VLT ball cutter has outstanding performance in reducing the milling force,and the milling forces in the x and y directions have decreased significantly,9.71% and 9.6%,respectively.In the transition zone,the smallest wear depth is the area occupation rate of 30%.MGT type ball cutter is 6.02 μm,with a decrease of 31.3%.Finally,the milling experiment of cutting the aluminum alloy Al6061 with a coated textured ball-end milling cutters was carried out.With reference to the milling scheme used in the simulation,five textured ball cutters were prepared,and TiXCo3 thin films were magnetron sputtered using PVD coating technology.After inspection,they were put into milling.The research results show that the introduction of texture effectively enhances the milling performance of the coated ball cutter,and the VLT ball cutter with an area share of 30% is more excellent in reducing the milling force and the milling temperature.