Simulation On The Thermal Field Of Wire Electrical Discharge Machining In Gas Based On ABAQUS

The Wire-Cutting Electrical Discharge Machining in gas(dry-WEDIM)has many advantages such as low surface roughness,high linear precision,narrow discharge gap,no electrolytic corrosion on the surface of workpiece and so on.It’s suitable for using multiple cutting process and finish machining.But researchers found that it’s a complicated process of electric physical change,existing problems of machining efficiency and speed because of lacking accurate prediction.So it’s necessary to make deeper research on the discharge mechanism of WEDM.In view of the problem of single-pulse discharge thermal field in WEDM,physical model and mathematical model of single pulse WEDM are built.It is considered the effect of the heat conduction and heat convection on the simulation results,and the equivalent specific heat method is to deal with the phase transition in the simulation process.The distribution of the transient temperature field and thermoelectric coupling field are analyzed through the ABAQUS software as well as DFLUX subroutine.The material is removed mainly by the thermal impact in the discharge initial stage.The gasification plays the leading role and the temperature gradient increases gradually and then decreases with the increase of the time.The EPOT of workpiece becomes weakened gradually and changes greatly along the depth direction of electric corrosion pit,in order to determine the distribution of discharge point locations to provide the theoretical basis during discharge process.The error rate of radium and depth of electric erosion pit modified by white layer in simulation is less than 10%,comparing with experimental data.And calculates the back viscosity volume of electrical etch pit in gas under precision machining conditions.On the basis of the single pulse temperature field simulation,the temperature distribution of the continuous pulse discharge point is simulated on the condition of the machining conditions in gas,analyzing the overlap volume proportion of the electric corrosion pit through the MATLAB fitting data,the morphology of electric corrosion crater is affected by the discharge point.When wire-cutting speed is certain,superposition volume between electric corrosion pits is affected by peak current and pulse width.Using the experimental data to calculate and analyze electric corrosion pits how to distribute on the machined surface.