Avaliação experimental do desgaste de canto durante o processo de eletroerosão do AISI H13

Abstract

The manufacture of molds and dies are rich in detail and complex geometries, requiring more innovative and precise technologes. One of the processes that stands out in the manufacture of molds and dies, is to EDM by penetration (Electrical Discharge Machining - EDM). The cutting by electrical discharge is classified as a non-defined geometry manufacturing process where material removal is carried out by repeated electrical discharge between two electrodes electrically conductive. The tool wear is a major measurement parameters in machining performance by EDM. The biggest problem caused by the electrode corner wear is the tool geometry change during the machining by changing the geometric tolerance and dimensional cavity. This paper proposes dimensional evaluation of the electrode corner wear, during the machining of the EDM process, varying the front surface of the electrode angle. Another purpose is to create an index, called rounding rate, which takes into account the areas of electrode corner wear due to the removed area of the workpiece material. The results showed that the copper electrode, copper tungsten and graphite, has a large corner radius growth at the beginning of machining, stabilizing these values with higher process time. The front surface of the electrode angle influence directly on the electrode corner wear. Graphite electrodes showed no corner wear rounding behavior during the tests. For rounding rate index tungsten copper electrodes had the lowest value presented in the machining of AISI H13.