The performance of surface textured SiAlON ceramic cutting tools on turning operation of Inconel 718

In recent studies, it has been observed that wear resulting from friction and high force generation can be effectively controlled by reducing the tool-chip contact area through the application of patterns with varying geometries at the micron and nano-scale on the rake or flank faces of inserts used in manufacturing operations. However, most of these studies have primarily focused on carbide inserts under low cutting speeds, and there has been limited exploration of surface texturing for ceramic inserts capable of withstanding high cutting speeds. This Ph.D. thesis aims to investigate the performance of SiAlON inserts, which are widely utilized for high cutting speeds in machining difficult-to-machine materials like Inconel 718, through surface texturing applied to the rake face. Micro-scale patterns were generated on the rake face of SiAlON inserts using femtosecond and water jet guided laser systems, employing biomimetic approaches such as linear grooves and arc-shaped geometry. The thesis extensively examined the effect of laser parameters on the formation of linear grooves, considering the inherently low fracture toughness values associated with ceramic inserts. Detailed investigations were carried out to optimize the laser parameters accordingly. The performance of the inserts, produced after the optimization of laser parameters, was experimentally and simulatively evaluated using finite element analysis in high-speed turning operations of Inconel 718. Comparative analyses were conducted with non-textured inserts to assess the impact of surface texturing. The results showed that inserts with arc-shaped grooves exhibited better wear resistance compared to non-textured inserts in improving high-speed machining performance, depending on the distance from the cutting edge and cutting conditions. It has been demonstrated that with new designs and lower-cost manufacturing techniques, surface texturing can be applied to ceramic inserts without affecting the final properties and has the potential for industrial use.