Numerical Simulation Of Temperature Field For High Current Pulsed Electron Beam Surface Modification

Based on the modification materials:steel, magnesium and aluminum this dissertation focus on the thermal effect of the surface modification by High Current Pulsed Electron Beam (HCPEB).First, non-linear and non-equilibrium heat conduction equations are used to fully describe the transient temperature field induced by HCPEB bombardment, considering the characters of high current pulsed electron beam energy deposition, a temperature field model for HCPEB surface modification was built. Then make use of Alternating Direction Implicit differential method to disperse them and to simulate the temperature fieldThe temperature fields in surface layer of steel, magnesium and aluminum when irradiating by HCPEB with accelerating voltage 23.4 kV,27 kV and 30 kV were simulated. Furthermore, the feature data including melting depth, temperature changing rate and solidification rate were obtained by data analyses. The results showed that the melting thickness will increase when using higher accelerating voltage, while the temperature changing rate and the solidification rate decrease correspondingly. The temperature changing rate in surface layer of these three materials all reach-109 K/s. For the accelerating voltage of 23.4kV, the solidification of steel rate is 4m/s, the solidification rate of magnesium is 6.6m/s, and the solidification rate of aluminum is 9.4m/s. The temperature field simulation of HCPEB surface modification provides a useful method for technique analysis to give an appropriate choice for melting depth, solidification and cooing rates.