An investigation of the effects of laser texturing parameters on textured ceramic tools applied in hard turning

Abstract

. Textured tools have the potential to reduce friction and temperature in the cutting zone, promoting lower machining force, tool wear and surface roughness. Nevertheless, the use of textured ceramic tools remains a challenge, mainly due to the difficulties related to the texturing process of these materials that can cause the embrittlement of the tool cutting edge. Therefore, the selection of suitable laser texturing parameters is essential to obtain textured tools with good properties to withstand the tribological conditions in the machining process. In this scenario, this research investigated the impact of laser texturing parameters on the performance of textured ceramic tools in turning. Textured tools manufactured with different laser parameters were evaluated in turning of the hardened steel AISI 4340 (55 HRC) by studying the tool wear. The texture on the mixed-ceramic tools were fabricated with a nanosecond pulsed ytterbium fiber laser. It was found that the laser texturing process has a great influence on the performance of the tools, since the laser parameters cause different levels of thermal damage to the ceramic material. There is a heat input limit from which the modifications caused in the ceramic material make turning unfeasible. Textured tools produced with a pulse duration of 8 ns and laser power of 30 W presented premature failure while tools manufactured with 2 ns and 50 W showed stable behavior during turning. Moreover, the number of laser scans also impacted the tool performance. At 2 ns and 50 W, the highest number of scans (1000 scans) promoted higher changes in the ceramic material, causing higher tool wear in turning. On the other hand, the smallest number of scans (11 scans) created minimal superficial textures, which were easily removed by abrasion wear. The best tool performance in turning was found for the textured ceramic tools manufactured with 2 ns, 50 W and 333 scans.