Si3N4 ceramic cutting tool sintered with CeO2 and Al2O3 additives with AlCrN coating

José Vitor Candido Souza, Olivério Moreira de Macedo Silva, Maria do Carmo Andrade Nono, João Paulo Barros Machado, Marcelo Pimenta, Marcos Valério Ribeiro
2011 Materials Research  
Ceramic cutting tools are showing a growing market perspective in terms of application on machining operations due to their high hardness, wear resistance, and machining without a cutting fluid, therefore are good candidates for cast iron and Nickel superalloys machining. The objective of the present paper was the development of Si 3 N 4 based ceramic cutting insert, characterization of its physical and mechanical properties, and subsequent coating with AlCrN using a PVD method. The
more » ... tion of the coating was made using an optical profiler, XRD, AFM and microhardness tester. The results showed that the tool presented a fracture toughness of 6.43 MPa.m 1/2 and hardness of 16 GPa. The hardness reached 31 GPa after coating. The machining tests showed a decrease on workpiece roughness when machining with coated insert, in comparison with the uncoated cutting tool. Probably this fact is related to hardness, roughness and topography of AlCrN.
doi:10.1590/s1516-14392011005000077 fatcat:57x4irst3vd3tpd445ft5u23cq