Performance modeling and multi-objective optimization during turning AISI 304 stainless steel using coated and coated-microblasted tools

Introduction. High-speed machining of stainless steel has long been a focus of research. Due to characteristics such as low thermal conductivity and work hardening, AISI 304 is considered to be a difficult material to cut. Machinability indicators provide important information about the efficiency and effectiveness of the machining process, enabling manufacturers to optimize their operations for increased productivity and precision. The purpose of the work. Coated carbide tools are most often used for machining AISI 304 stainless steel. Few studies, meanwhile, have examined the effects of pre-and post-treated coated carbide tools when turning these alloys at high speeds. In addition, only a small number of studies have simultaneously optimized the cutting parameters while employing pre -and post-treated tools. The methods of investigation. The present work comparatively evaluates the performance of coated and coated-microblasted tools during the turning of AISI 304 stainless steel. The tools were PVD-AlTiN coated, PVD-AlTiN coated with microblasting as a post-treatment (coated-microblasted), and MTCVD-TiCN/Al2O3 coated (MTCVD). The experimental-based mathematical models were developed to predict and optimize the turning performance. Results and Discussion. In this study, it is found that PVD-AlTiN coated tools have the lowest cutting forces and surface roughness, followed by PVD-AlTiN coated-microblasted and MTCVD-TiCN/Al2O3 coated tools. However, there is no significant difference observed in these responses for coated and coated-microblasted tools. It is found that the cutting forces increased with feed and depth of cut while decreasing with cutting speed. However, this effect is significant for MTCVD-coated tools. On the other hand, higher tool life is observed with MTCVD-TiCN/ Al2O3 coated tools, followed by PVD AlTiN coated-microblasted and PVD-AlTiN coated tools. Tool life was largely affected by cutting speed. However, PVD-AlTiN coated tools exhibited this effect more noticeably. The models, with correlation coefficients found above 0.9, can be utilized to predict responses in turning AISI 304 stainless steel. The optimization study revealed that turning AISI 304 stainless steel with MTCVD-TiCN/Al2O3 coated tools incurs lower cutting forces of 18-27 N, produces a minimum surface roughness of 0.3-0.44 mu m, and has a better tool life of 36-51 min compared to PVD-AlTiN coated (C) and PVD-AlTiN coated-microblasted (CMB) tools.