电火花诱导可控烧蚀加工不对称蚀除现象研究

摘要

为了研究电火花诱导可控烧蚀加工出现的工件蚀除率高，电极相对损耗低的不对称蚀除特点，本文进行了试验研究，包括放电极性和氧气压力2个因素。结果表明：在电火花诱导可控烧蚀加工中，电火花放电使得两极能量分配不均，并在两极形成不同量的金属活化区；通入的氧气与活化区金属发生反应，释放的热能又大大加剧了这种不均衡现象，最终表现为这种不对称蚀除现象；烧蚀加工中的放电过程为氧气中的电火花放电，其蚀除材料以电子轰击作用为主；使用正极性加工对提高工件材料蚀除率，降低电极相对损耗率有重要的作用；一定的氧气压力对这种不对称效应也有促进作用。%In efforts to figure out the controllable spark⁃inducing combustion's high material removal rate and low relative electrode wear rate, the research team has conducted experiment on the parameters: the working polarity and the oxygen pressure. The result shows that, in the case of controllable spark⁃inducing combustion, discharging distributes the energy between the electrodes unevenly, and forms different scales of metallic activation zones on the electrodes. It was also discovered that the injected oxygen reacted with the metal in activation zones and the released heat energy made the energy even more unevenly distributed and eventually this asymmetric erosion phenomenon appeared. In the discharging process during combustion and erosion, the electronic bombardment takes the main role in the discharging process;normal polarity machining is of great significance to the high material removal rate and low relative electrode wear rate; and the oxygen with a certain pressure was found helpful to this asymmetric effect.