电子束扫描对金属表面温度场的影响

Influence of Electron Beam Scanning on Temperature Field of Metallic Surface

电子束用于金属表面抛光,能有效去除金属表面的微缺陷,提高材料性能,从而延长工件的使用寿命。采用低功耗的赝火花放电装置可产生高频高密度的电子束,用于金属表面处理。然而,入射电子束能量的非均匀分布和扫描过程中工艺参数的不合理选择等会导致金属表面层上的温度场不均匀,进一步可能导致工件中产生残余应力,影响抛光后的表面质量。利用APDL对电子束抛光过程中的工件表面温度场进行了仿真分析。在考虑束源能量不均匀的情况下,分别研究了扫描过程中的束源功率、束斑重叠率和扫描次数三个主要工艺参数对表面温度场的影响,这将有利于获得更优的工艺参数组合,从而获得更好的表面质量和更高的加工效率。

Electron beam,which is used for metal surface polishing,is capable of eliminating surface micro-defects and improving material performance to prolong the service life of workpieces.High-frequency high-density electron beam can be generated for metal surface treatment with low-power pseudo-spark discharge device.However,the non-uniform distributions of the electron beam energy and the irrational selection of process parameters can cause the non-uniform temperature field on the metal surface layer.This non-uniformity temperature field causes residual stresses in workpieces,thus adversely affecting the metal surface quality after a polishing treatment.The surface temperature field during a beam treatment process is simulated by the ANSYS parametric design language(APDL).Influences of the three parameters on the surface temperature field distributions are investigated,including the beam power,beam spot overlap rate and number of scans.Knowledge of the effects of each parameter on the temperature field distribution can be used to obtain optimal combination of process parameters to achieve better surface quality and higher processing efficiency.