Einfluß des Kohlenstoffgehalts auf Gefüge und Eigenschaften nickellegierter Einsatzstähle

Abstract

The case carbon content influences predominantly microstructure and important properties of carburized components. Microstructures and performance in slow bend and impact tests have been investigated with case carbon contents of 0.7%, 0.85% and 1.0% and 15CrNi6, 14NiCr14 and 14NiCr18 steels. Retained austenite and surface hardness are influenced significantly with case carbon contents higher than 0.85%, case carbon contents between the optimum of 0.6-0.7% for maximum hardness and 0.85 % therefore can be tolerated. The influence of nickel content on microstructure and hardness is independent on case carbon content. The ductility of the carburized microstructures as shown by the bending stress at crack initiation increases with increasing case carbon and nickel content, assuming that stress conditions enable the stress induced transformation of retained austenite into martensite.