Numerical Simulation And Parameter Optimization Of High Speed Steel Taper Tapping Process

Tap, named as a kind of common cutting tool is used to machine the internal thread. Tapping is a semi-closed machining under the mal-condition and low cutting efficiency. Unreasonable cutting condition can increase the torque, axial cutting force and cutting temperature, and causing consequences by adhering the tap, breaking the cutting edge and so on. It has been given a lot of attention in the area of changing geometric parameters, changing cutting parameters and selecting high quality materials for high speed steel tap tapping process. In our country, it is relevant late to focus on the HSS tap tapping process still at home. Therefore, to save much time and money, selecting the simulation of the treatment process has a broad prospect for development, and it has become an inevitable trend. Because of the correction between the simulation and real test is difficult to achieve, so It has a slowly development about selecting the finite element analysis method for tapping process.High speed steel tap tapping process is the object of the research. The cost of high speed steel tap tapping is reduced and its effect is improved by reducing torque, axial cutting force and cutting temperature in the process of tapping. The model of tap is completed with Pro/E and simulation of treatment are with the help of the theory of heat effect, equation of motion, sub-cycle and tool-chip contact, and the 3D simulation tapping process function of AdvantEdge FEM. The tap material is HSS/Co-M35, and the size of H13 hot-work die steel and titanium alloy Ti-6Al-4Vworkpiece are 20mm×20mm×10mm. Researches focus on the followings:(1) Three-dimensional modeling on tap with Pro/E, and modeling by changing the geometric parameters of the tap (hook and relief angle) and the structure parameters (passivation edge radius), etc.(2) Based on the theory of heat effect, equation of motion, sub-cycle and tool-chip contact, pre-treatment of simulation include setting the workpiece, tool and cutting parameters has finished in tapping process of numerical simulation. Tap and workpiece are meshed as well. At last, its reliability is verified by the torque value and chip obtained from the test.(3) Through the AdvantEdge FEM, cutting force empirical model of cutting force is established and its influence of different parameters is analyzed. Also, the research on the maximum cutting force and torque under three materials (A12024-T4 aluminum alloy, HI3 hot-work die steel and titanium alloy Ti-6A1-4V) are compared.(4) In the process of titanium alloy Ti-6A1-4V tapped by HSS/Co-M35, the cutting temperature cloud of cutting area, rake face and flank face is studied, and establishing the history curve of cutting temperature along the cutting edge. Peak tool temp is compared when taking different passivation edge radius and relief angles. The impact of tapping performance under the whole life cycle parameters of tap which contain hook and relief angle (tool design parameters), passivation edge radius (tool manufacturing parameters) and main spindle speed (tool cutting parameters) are studied by the multi-target orthogonal test design. Three tapping performance indexes which are maximum torque, axial cutting force and cutting temperature have been converted into a single composite indicator yi by using the comprehensive evaluation method.This topic research is supported by Natural Science Foundation of China, the project number is:51275333.