Investigation and Optimization of Cutting Performance of High Chrome White Cast Iron by Wire Erosion

Abstract

Wire electric discharge machining (WEDM) is an emerging approach to producing more accurate and precise complex products in the unconventional machining process. The WEDM process is affected by several process factors. Therefore, the appropriate combination of process factors is required to achieve economical and quality machining. Machining is very difficult due to the presence of chromium carbide in the structure of high-Cr white cast irons (HCCIs) with 12–17% Cr content in machining processes. Therefore, the machinability of HCCIs has always been a disadvantage. In this study, specially molded HCCIs samples were subjected to softening, casting (not heat treated) and hardened heat treatment processes, respectively. We aimed to experimentally investigated the changes in HCCIs samples characteristics, pulse on time, pulse of time, wire speed, and cutting performance in the WEDM process in this study. The L18 orthogonal array was used using the Taguchi method, and an experimental study was prepared. Afterward, an optimization study was carried out using mathematical models for WEDM with the help of performance outputs via ANOVA analysis. The experimental performances examined in this study are material removal rate and surface roughness. The experimental study determined that the material removal rate and surface roughness increased when the pulse on time increased. Later, machined samples morphological and structures properties were analyzed X-ray spectroscopy (EDS), scanning electron microscopy, microhardness and surface roughness. Furthermore, electrical conductivity of them was measured. © 2023, King Fahd University of Petroleum & Minerals.