Design And Manufacturing Research On Crown Ball End Milling Cutter For Hardened Steel Processing

Hardened steel is widely applied in car cover mold industry because of its remarkable advantage of high hardness, low elongation, low plasticity and easy to form high finish machining surface. However, due to the large hardened steel mold the characteristics of high hardness, surface features of complex, cutter wear and damaged is caused because of large cutting load and variable in the processing, thereby this led to lowering mould processing surface quality, the new challenge on cutting tools is puts forward. The crown ball milling cutter design and preparation technology is researched in this paper for the cutting stability and the surface quality of the cutting tool in machining hardened steel.Firstly, the cutting characteristicsis of ball end milling cutter and ring milling cutter is analyzed, the crown ball end is designed for hardened steel processing. The mathematical model of contour surface and the helical line of crown ball end milling cutter is established for non-standard cutter multi section spiral cutting edge smooth transitional connection through integration, differential geometry. The simulation of mathematical model of profile and cutting edge line is impleted through MATLAB software.Secondly, according to the structural features of crown ball end milling cutter, the grinding process is researched, cutter grinding technology is enacted. The grinding trajectory mathematical model of spiral groove and rake of crown ball end milling cutter is established through envelope theory. The grinding trajectory mathematical model is impleted through simulation software.Thirdly, the grinding and precision test of crown ball end milling cutter is carried out, the accuracy of mathematical model is proved by simulation of spiral groove and rake. The smooth transition of the cutting edge of spiral groove and the rake face of crown ball end milling cutter is realized.Finally, the cutting performance of ball end milling cutter and crown ball end milling cutter is analyzed. The results show: the crown ball end milling cutter can improve the stability of cutting and improve the surface quality of the workpiece in the premise of ensure the cutting efficiency. Especially in the processing slope 10°~30° curved surface, the crown ball end milling cutter show a more excellent cutting performance.Not only is the methods of crown ball end milling cutter design preparation provided in this paper, but also the cutting performance of crown ball end milling cutter is analyzed. It is vital significance for the promotion and application of crown ball end milling cutter.