Research Into High Efficiency And Low Wire Wear Machining Technology Of WEDM-HS

In this paper the machining technology with high cutting rate and low wire wear in WEDM-HS has been developed. The main problems of WEDM-HS machine tools have been analysed in detail. How to solve this problem is discussed and some solutions are put forward.Firstly the effects of current waveform on the machining performances are investigated. The results show that the slop-waveformed pulses can share the discharge energy in the gap better. Based on the study of the machining mechanism of WEDM, how the current slop affects the cutting rate and wire wear is pointed out. By the experiments the characteristics of ignition delay time are studied, then how the ignition delay time changes the current waveform is discussed.Secondly defects of the traditional pulse generators are analysed by which a new pulse generator is designed with MCU, including the main circuits of MCU, breaking off circuit, amplifying circuit and accelerating circuit . The control software is programmed. A circuit board is finished and adjusted. The waveform produced by pulse generator is stably and vibrates little. It can cut off rapidly and the slop of the current can be adjusted freely.At last a lot of experiments are performed using the pulse generator. From these experiments the questions below are discussed: whether there is a best current slop to make machining in high cutting rate and low wire wear; what factors affect the best current slop; which factor is the most influential on cutting rate among current slop, pulse length and current, and by orthogonal design the selection of these parameters is given.In this paper the effect of current slop on the distribution of discharge energy in the gap of WEDM is researched for the first time in theory, and some rules are found. Based on the theoretical research a pulse generator is designed and works well in the experiment.