Research On Modeling And Process Optimization Of Wire Electrical Discharge Machining Ti-6Al-4V

Titanium alloy is one of the alloy materials widely used in aerospace and other fields.Because of its complex material properties,it is easy to cause adhesion and damage of cutting tool and material when using traditional processing methods such as turn milling to process titanium alloy.Wire electrical discharge machining can remove the material through the discharge between the electrodes,and the electrode wire is not in contact with the work piece,so it is a more suitable method for titanium alloy machining.The discharge process of WEDM is complex,so it is very difficult to establish a reasonable theoretical analysis model.At the same time,there is a lack of processing parameters of titanium alloy in WEDM,so it is necessary to determine the appropriate processing parameters to improve the processing quality and efficiency.In this paper,the EDM process of titanium alloy Ti-6Al-4V is studied by using the low speed wire electrical discharge machining machine.Based on the in-depth study of the machining mechanism,the machining parameters and process optimization are studied.Firstly,based on thermal analysis,the mathematical model of temperature field of single pulse discharge is established;Secondly,the temperature field of pulse discharge under the action of moving heat source is simulated by finite element method,and the surface roughness and material removal rate are predicted according to the temperature distribution data;Finally,cutting experiments are carried out to explore the influence of processing parameters on surface roughness and material removal rate;The response surface method is used to analyze the optimal process parameters combination of titanium alloy WEDM,and the optimization effect of multiple cutting on the machined surface is explored.The main contents of this paper are as follows(1)On the basis of consulting the relevant literature at home and abroad,this paper summarizes the research status and latest progress of EDM mechanism,modeling method and WEDM parameter optimization,and determines the research content and main research methods of the subject.(2)The theoretical prediction model of WEDM is established.The mechanism of WEDM is studied,and the mathematical model of temperature field of single pulse discharge is established.The theoretical model is solved by using software,and the change law of pit size and temperature is obtained.The shape,size and superposition mode of the pits are analyzed,and the calculation models of surface roughness and material removal rate are established.(3)The simulation model of WEDM process is established.The finite element analysis software is used to simulate the temperature field of single pulse discharge,and the change rule of the theoretical model is verified.The temperature field formed by pulse discharge under the action of moving heat source is simulated and compared with that of single pulse fixed heat source;The temperature field of continuous pulse discharge was simulated,and the surface roughness and material removal rate of pits were obtained.(4)The experiment of WEDM was carried out and the influence of process parameters was analyzed.The effects of pulse width,pulse interval,no-load voltage,peak current,wire speed and feed speed on the surface roughness and material removal rate in the process of WEDM were analyzed,and the prediction ability of the model was proved.(5)Parameter analysis and optimization of WEDM for titanium alloy.The response surface method is used to obtain the minimum surface roughness,the maximum material removal rate and the combination of the two processing parameters.The accuracy of the optimization results is proved by experiments;Multiple cutting experiments are designed and the optimization effect of multiple cutting strategy on machined surface is analyzed.In this paper,the influence of process parameters on the surface roughness and material removal rate is studied,and a more accurate WEDM prediction model is established to determine the combination of process parameters for machining Ti-6Al-4V work piece.The research content has guiding significance for improving the efficiency of WEDM,and the research results provide an important reference for the selection of parameters in WEDM of titanium alloy.