Innovative Einsatzstähle als massgeschneiderte Werkstofflösung zur Hochtemperaturaufkohlung von Getriebekomponenten. Diskussion

The development of new process technologies forthe carburization of gear components at a temperature of 1050 °C, as opposed to the currently used temperature of 930 °C, requires the implementation of innovative material solutions to retain a fine grained structure prior to hardening and thereby ensure optimal mechanical properties. Within the scope of this investigation, laboratory melts were produced, which are based on the conventional case-hardening steels 16MnCr5, 22CrMoS3-5 and 17CrNiMo6, but with varying contents of the micro-alloying elements Al, Nb, and Ti. This investigation focused not only on the grain growth behaviour of these steels at high temperatures, but also on the influence of the micro-alloying elements on the mechanical properties and castability (continuous casting). Carbo-nitrides niobium, titanium and aluminium containing inhibit grain growth. The results of this study show that it is possible to produce case-hardening steels which are resistant to grain growth up to a temperatures of 1150°C.