PERFORMANCE OF WATER AND HYDROCARBON DIELECTRICS IN WEDM OF CEMENTED CARBIDE

Abstract

In alignment with the United Nations Sustainable Development Goals (SDGs) 9 and 12, the global manufacturing industry continuously seeks productive, responsible, and sustainable solutions. In this context, the electrical discharge machine has shown strong potential for processing materials with low machinability, such as superalloys and conductive ceramic-based materials, due to its ability to remove material without tribological contact. Among these, cemented carbide stands out for its high wear resistance, consisting of tungsten particles in a non-oxide ceramic phase (WC) bonded by a metallic phase (Co), resulting in elevated hardness and mechanical strength at high temperatures. However, literature presents limited studies on the WEDM of such materials using a reciprocating molybdenum wire, and even fewer when considering the influence of different dielectrics. This study aims to evaluate the behavior of deionized water and hydrocarbon-based dielectrics in the WEDM of WC-Co, focusing on their effects on process performance and surface integrity. Five levels of lateral infeed (Δy) were tested under constant discharge energy and fixed machining parameters. The results demonstrated that increasing the lateral infeed led to a reduction in material removal rate. The hydrocarbon dielectric achieved the highest wire feed rate at Δy = 100%, resulting in an 88.5% increase. Conversely, when Δy was reduced, deionized water yielded superior productivity, with a 53.5% improvement. Additionally, surface texture analysis showed a reduction in average roughness (Sa), indicating greater process stability and reduced morphological distortion with deionized water at Δy = 10%, representing a 10.3% improvement over the hydrocarbon-based dielectric. Future work will explore the effects of the recast layer on distinct grade discharge energies to optimize performance across broader machining conditions.