The Influence of Edge Preparation on the Performance of Ceramic Inserts Applied to Hard Turning

The need for mechanical components with superior strength and specific characteristics for application under severe conditions requires materials with satisfactory mechanical strength and wear resistance under elevated loads. Hardened steels present suitable properties for these applications, thus, manufacturing processes must be capable of dealing with these characteristics to produce high quality components. The aim of this work is to investigate the influence of the cutting conditions (cutting speed and feed) and cutting edge preparation (chamfer angle) of mixed alumina tools (Al₂O₃ + TiC) when turning hardened AISI 52100 bearing steel (62 HRC), with emphasis on the turning force components, machined surface finish and tool life. The results indicated that feed statistically affected all the evaluated parameters (increasing cutting, feed and passive forces and roughness), whereas cutting edge preparation affected only the feed force and surface roughness (lower feed force and roughness obtained using the tool with a chamfer 80 μm wide and angle of 30º). Regarding tool life, the commercial tool and the tool prepared with chamfer width of 80 μm and angle of 30º presented superior performance and allowed gradual tool wear evolution, in contrast with the other cutting edge preparations which led to edge fracture.