Investigation on diamond wire break-in and its effects on cutting performance in multi-wire sawing

Multi-wire sawing with diamond wire is used to slice hard and brittle materials such as sapphire, silicon carbide, or silicon into thin wafers. Compared to traditional slicing methods, multi-wire sawing with diamond wire has many advantages, including reduced kerf loss, efficient machining, and improved form accuracy. However, the process is associated with several unexpected problems, including considerable kerf loss and inefficient cutting during the initial cutting step. Thus, materials cannot be constantly removed due to the instability of the cutting performance of the diamond wire. These phenomena are defined as the break-in characteristics of diamond wire. This paper focused on the break-in characteristics of diamond wire and the effects of these characteristics on the cutting performance. In an experiment, a single-wire sawing machine equipped with a monitoring system was used to analyze the horizontal and vertical cutting forces which arose during the cutting process. The cutting performance was evaluated by means of cutting profile measurements. The wires used were analyzed by the newly developed vision measurement system and through scanning electron microscope (SEM) imagery. On the basis of results, it was found that the break-in characteristics of diamond wire are strongly correlated with the wear behaviors of the diamond wire.