Shape-cutting of quartz glass by spark discharge-assisted diamond wire sawing

Shape-cutting of quartz glass is difficult due to its high hardness, brittleness, and electrically insulting properties. This paper explores shape-cutting of quartz glass by spark discharge-assisted diamond wire sawing. The spark discharges were generated around diamond wire based on wire electrochemical discharge machining (WECDM). In the NaOH electrolyte, chemical etching of quartz glass took place with the occurrence of spark discharges. The chemical etching products were immediately removed by the quickly moving diamond wire. The diamond wire could keep straight with appropriate process parameters, which is essential to ensure machining accuracy. Experiments were conducted to analyze the effects of applied voltage, wire speed, and workpiece feed rate on machining performance. The diamond wire bending was measured to study the cause of poor machining accuracy. In addition, the overcut by spark discharges was presented close to the workpiece surface. To solve this problem, two thin soda-lime glass plates were put on the top and bottom surfaces of the quartz glass. As a result, the overcut only existed on the soda-lime glass, and good machining accuracy was achieved on quartz glass.