A Study on Machining Characteristics of Silicon Nitride with Spline Members in Laser-Assisted Turn-Mill

Laser Assisted Turning (LAT) is an effective machining method for difficult-to-cut materials, such as nickel and ceramics. LAT has several advantages, including low manufacturing costs, high productivity and high quality machining of various kinds of materials. However, LAT is in the early stage of applications and has only been used for limited round members only. Therefore, a laser assisted turn-mill (LATM) process that is capable of machining various workpiece shapes is proposed to complement LAT in this paper. In this paper the temperature distribution according to the rotation of the workpieces was effectively predicted. The effect of preheating was verified by analyzing the results of thermal analysis and experiment. Also, a new preheating method based on laser power level is proposed. It was determined that the heat produced by the proposed preheating method can be efficiently transferred into the workpiece, and the effectiveness of the LATM process was verified by machining Si3N4.