In the deformation and cutting process of semiconductors and ceramics, especially brittle materials such as silicon carbide (SiC), the presence of high pressure phase transformation (HPPT) is of great importance for accomplishing ductile regime machining (Patten 2007). To augment the ductile regime machining of these nominally brittle materials, the high pressure phase can be preferentially heated and thermally softened by using concentrated energy sources such as laser beams (Dong 2006). In this research, the effect of the pressure and temperature and the interactions of these two factors on the micro-laser assisted machining (µ-LAM) process are studied by using a hybrid machining system that consists of a diamond stylus (tool) and infrared (IR) fiber laser heating source. The combinations of loading (pressure) with and without laser heating prior to loading are studied at various cutting depths and speeds. The laser achieves heating and thermal softening as evidenced by the increased ductility of the material. Notably, the results of scratch tests at 1 µm/sec show a doubling of the scratch depth which suggests a ~50% reduction of hardness due to thermal softening by the laser heating. The results are studied by atomic force microscopy (AFM) and confirmed with white light interferometer microscopy to verify the experimental results. Published in the Transactions of NAMRI/SME
, Vol. 37, 2009, pp. 75-80.