1. Introduction
Wire electrical discharge cutting (WEDM) is a recognized non-traditional material removal process used to manufacture components with complex shapes and cross-sections. It is regarded as a unique modification of the conventional electrical discharge machining (EDM) process - the conventional electrical discharge machining (EDM) process uses electrodes to initiate the spark discharge process, while the WEDM process uses continuously wired electrode wires (determined by the diameter Made of fine copper, brass or tungsten (0.05–0.3 mm), this wire enables very small corner radii. Utilize mechanical tightening equipment to maintain tension on the electrode wire, reducing the possibility of producing inaccurate parts. In the WEDM processing process, the material at the front end of the electrode wire is corroded, and there is no direct contact between the workpiece and the electrode wire, thus eliminating mechanical tension during the processing. In addition, the WEDM machining process enables the processing of specialty materials and high-strength, heat-resistant materials, eliminating the geometric changes that occur when processing heat-treated steel.
WEDM was first introduced into the manufacturing industry in the late 1960s. The development of this process was the result of a search for new technologies to replace the machining electrodes used in the EDM process. In 1974, D.H. Dulebohn used a ray tracing system to automatically control the shape of components to be processed by the WEDM process. By 1975, the process was rapidly gaining popularity as the process and its superior capabilities were better understood by the manufacturing industry. In the late 1970s, computer numerical control systems were introduced into the WEDM process, which brought great changes to this processing technology. Therefore, the various potentials of the WEDM machining process are fully exploited, and various through-hole processing can be carried out through the electrode wire - which must pass through the component to be processed. Common applications for WEDM include the manufacture of stamping and extrusion tools and dies, jigs and gauges, prototypes, aircraft and pharmaceutical components, and grinding wheel forming cutters.
This article is a companion piece to the paper on open-mold discharge machinery by Ho and Newman [3], which reviews various academic research fields including WEDM processing technology. This article first reviews this processing technology based on recognized principles of thermal conductivity and its applications. The main part of this article focuses on the main research activities of WEDM, which includes WEDM processing process optimization and WEDM process monitoring. The final part of this article discusses these topics and hints at future research directions in WEDM.