Avaliação do desempenho de fluidos dielétricos no processo de usinagem por descargas elétricas

Abstract

The Electrical Discharge Machining process is very useful while machining very hard materials, which are very difficult to be machined by traditional processes, while can make complex geometries and minimum dimensions. One of the materials that are used in this process is highspeed steels, which are very hard and has a high mechanical resistance. The main objective of this work is the study of performance of different dielectric fluids used in EDM in different cut conditions in terms or metal removal rate (MMR) and wear ratio (WR) roughness parameter (Ra). A discuss of the most important factors that can produce different performance when machining with this process is presented. Five tests with different types of dielectric fluids using a cooper tool were carried out. Was noticed different performance between the fluids, which all the other conditions of operation were unchanged. According to the fluid the workpiece presented less roughness and a higher MMR in some cases. In other cases, a higher MMR produced in the other hand a recast layer less uniform. The most important conclusion of this work is about kerosene, which costs 3 times less than the specific dielectric fluids for EDM, presented worst finishing surfaces and not too high MMR as expected, despite all the risks for the operator.