Sisa O. Dimensional rough processing of hard-alloy forming rolls by electric arc

The thesis is devoted to development of technology and equipment of methods of dimensional rough processing of hard-alloy forming rolls by electric arc as a high-effective alternative to traditional methods of their rough processing. The substantiation of technological schemes of surface shaping of hard-alloy forming rolls by electric arc was made. Analytical relations of technological characteristics of rough processing of hard-alloy TC-15 in the conditions of implementation of various shaping schemes with the factors causing the processing mode and geometrical parameters of electrodes are established. Physical mechanism of electrical erosion under the conditions of bipolar dimensional arc processing taking into consideration the quality of heat sources on electrodes, polarity and process dynamics were investigated. Structural time analysis of bipolar dimensional arc processing was made as well as its continuation was specified. For the first time an energetic balance of bipolar electric arc in the conditions of dimensional arc processing of hard-alloy electrode couple was conducted. It was established that such an arc is an efficient heat source. There were suggested new technological solutions concerning extension of technological options of dimensional arc processing of forming rolls. It was elaborated, tested and recommended for implementation a high-efficient process of a single-polar rough dimensional arc processing of a hard-alloy forming roll.