能束加工的温度场叠加效应

Pile-up Effect of Temperature Field Generated by Energy Flux

建立了能束加工中连续脉冲作用的温度场叠加模型,提出了叠加效应的概念及其与热冲击应力的关系,从而揭示了连续脉冲作用产生的叠加温度场与单脉冲在温度和热应力分布上的不同及其对裂纹和加工速度的影响。最后用实验验证了叠加效应的存在。

Electrical discharge machining and laser beam machining all use thermal as final energy to process materials. The thermal models are similar and their thermal effects have something in common. Therefore they are considered together with a concept ＂energy flux＂ in thermal effects. Until now little is known about the effects of repetitive pulses on temperature and stress field in energy flux machining （EFM）. To explore it, a thermal model of repetitive pulses was developed and the pile-up effect of repetitive pulses was presented, by which the differences in temperature and stress distributions, as well as thermal shock, were analyzed between repetitive pulses and single pulse, and their effects on cracks and materials removal rate were discussed. Finally the pile-up effect was verified by experiments. Its function of reducing cracks is obvious.