Multi-objective Optimization Design Of Micro-textured Tools For Cutting Nickel-based Superalloy In Spray Cooling

Nickel-based superalloy GH4169 is a material with high hardness,high strength and high temperature resistance.Based on its excellent performance,the cutting performance of ordinary tools is poor when cutting it.In order to handle the above problems and optimize the cutting performance of the tools,the micro-textured tool was introduced.For different materials,different micro-texture morphologies and parameters will also have different degrees of influence on the cutting performance when cutting workpiece,and the same micro-texture morphologies and parameters have different effects on the cutting force,cutting temperature and tool wear.In order to promote the processing performance and efficiency of the tool processing nickelbased superalloy GH4169,this paper designed and processed micro-textures with different morphologies and parameters on the rake face based on the bionic theory.Through the combination of simulations and experiments,different micro-textured tools were used to cut nickel-based superalloy GH4169,and the effects of edge distance,diameter and spacing on the cutting performance of micro-textured tools were investigated.The surface response method and NSGA-Ⅱ optimization algorithm were used to optimize the micro-texture parameters,and the micro-texture parameters with the best comprehensive cutting performance were selected.The main research contents of this paper are as follows:Firstly,five kinds of micro-textures with different morphologies were designed.The micro-textured tools geometry models were established using UG.The process of GH4169 cutting with micro-textured tools with different morphologies and nontextured tools was simulated in DEFORM.According to the comparison of simulation results,the better micro-texture morphology was selected.Secondly,17 sets of micro-texture experiments with different parameter combinations were designed by Box Behnken method(BBD).The experimental cutting was carried out in spray cooling.According to the experimental results,regression models were established and variance analysis was carried out.According to the final regression model,the influence of each micro-texture parameter on the objective function was analyzed respectively.Based on the minimum cutting force,cutting temperature and wear area of the tool rake face,the response surface method was used to select the optimal combination of micro-texture parameters,and the micro-textured tools with optimal parameters were machined for cutting experiments.The reliability of the optimization algorithm was judged according to the error between the optimization results of the response surface method and the experimental results.Finally,combined with the NSGA-Ⅱ algorithm and the approximate model,the micro-texture parameters were optimized for multiple targets.27 groups of full factor experiments on micro-texture parameters were designed using Minitab.Under the same conditions,micro-textured tools were processed according to different microtexture parameters designed and cutting experiments were carried out.According to the experimental results,RBF and BP approximate models were established in MATLAB to compare the accuracy.On this basis,the micro-texture parameters were optimized by combining NSGA-Ⅱ algorithm and high-precision approximation model,and the Pareto solution set of micro-texture parameters was obtained.Then the results were compared with the multi-objective optimization results of the above surface response method,and the most suitable algorithm for multi-objective optimization of micro-texture parameters was selected.