Research On Turning Process Optimization Of TC11 Titanium Alloy Aerospace Disc Parts

TC11 titanium alloy is often used as disc parts in aero-engines due to its excellent material properties,but TC11 is also a difficult-to-cut material,its cutting performance is poor,and it has the difficult-to-cut characteristics of typical titanium alloys.In the cutting process,there are problems such as large cutting force,high cutting temperature,fast tool wear rate and poor processing quality.Secondly,the research found that in the existing research on cutting parameters for machining TC11 disc parts,there are few researches on the background of large depth of cut,low feed and low cutting speed.When using this cutting amount for machining,there exists problems that the changing laws of cutting force,cutting heat and the quality of the machined surface are ambiguous.Based on the turning of TC11 material disc parts,this topic discusses the changing laws of cutting force,cutting heat and machined surface quality under the background of large cutting depth,low feed and low cutting speed,and the cutting parameters are analyzed and optimally selected.The main research contents are as follows.A two-dimensional orthogonal cutting model was established,and single-factor experiments and orthogonal experiments were designed to study the distribution of cutting force and cutting heat on the tool and workpiece during the cutting process.The force-heat coupling phenomenon in the cutting process were analyzed,and the variation law of cutting force and cutting heat were given in combination with the selection of cutting amount,and the optimal cutting amount group was optimized.On the basis of the two-dimensional cutting model,a method of establishing a threedimensional turning finite element model was proposed,and the model could effectively simulate the turning process.Secondly,the friction coefficient was introduced in combination with the cutting depth and cutting speed,and the influence of different friction coefficients on the cutting process and cutting force was discussed,and the parameter selection of back engagement,cutting speed and friction coefficient were optimized by using an algorithm with the goal of minimizing the cutting force.Finally,for the dual objectives of the minimum cutting force and the maximum material removal rate,based on the orthogonal experimental data,the large depth of cut,low feed rate and low cutting speed were optimized and selected,and the optimal parameter group was obtained.The tool holder and machine tool connection fixture suitable for dynamometer were designed,and Kistler 9257 B dynamometer and CA6140 machine tool were used to build a turning experimental platform to verify the accuracy of the three-dimensional simulation cutting model.Secondly,the SK40 P machine tool was used to design the surface roughness experiment,the influence rule of cutting amount on surface roughness was obtained,and the empirical formula of surface roughness was fitted.Finally,taking the surface roughness and cutting force as the dual objectives,the cutting amount was optimized by using the non-dominated genetic algorithm,and the optimal parameter group was obtained.