Arithmetic And Experimental Study Of Electrode Wastage And Compensation In Micro-EDM

The study of processing three dimensional metallic micro-structures in micro machining is a hotspot in nowadays. Micro-electro-discharge machining (micro-EDM) is a very important method of micro machining. It has attached importance to a lot of scholars around the world. The problem that the electrode wears down badly is the keystone in the field of micro-EDM. Many scholars had done a lot of research in the field of tool wear compensation. They paid attention on processing technology to reduce wastage. Or design complicated detection and measurement system, and detect wastage and then feedback compensate. This article is written on the basic of theoretical modeling, and a new method of fix-length compensation has been developed. Based on the machining accuracy, we decide whether write compensation or not. The correctness of the theoretic analysis is validated by experiment. This paper mainly includes the following:Without compensation, we have established the outline model of which underside shape will change as electrode wearing down when machine single groove in monolayer. Because of the severe wastage, the underside of the workpiece is declining from the start-point to the end-point. And we have calculated the function relationship of machining depth and machining length. The experiment indicated that the machining depth decreases as the machining length increases, till the machining depth tends to become zero. The experimental results are in agreement with the presented theory.We also studied the method of fix-length compensation when machine single groove in monolayer. We have calculated when to compensate and how much to be compensated. From the experiment, the precision of the groove is good via applying the compensation method.We have analyzed the result of compensation when processing parameters changed, such as wear ratio, quantity of compensation, layered depth, the diameter of the electrode, discharge gap. We have got the effect law on processing accuracy when parameters changed.We have measured the wear ratio while machining the stainless steel use the tungsten electrode.We also have studied the method of fix-length compensation when machine arbitrary section. The method of fix-length compensation when machining single groove in monolayer is generalized to arbitrary section.