P. Kula, R. Atraszkiewicz, PhD, M. Górecki, PhD, E. Stańczyk-Wolowiec, Technical University of Lodz, Lodz, Poland
Field experience in vacuum carburizing has demonstrated many applications require a more precise control system that controls both case depth and automatically adjust the furnace cooling rate to achieve a pre-determined Vickers hardness. The Institute of Materials Engineering in cooperation with SECO/WARWICK S.A. developed the SimVaCPlus™ Hardness computer program to determine carburized layer hardness profiles after gas quenching (cooling).
When calculating cooling speed requirements (cooling pressure), the SimVaCPlusäHardness program takes into consideration the furnace cooling characteristics, load (charge) configuration, part geometry and carburizing case profile. The SimVaCPlusäHardness program reduces the heat treating process design time, and limits or even eliminates, trial cycles. While designing the cycle, the user can specify the surface layer properties criteria e.g. surface and limit hardness for effective case depth, an advancement in process technology compared to any program in use today.
The SimVaCPlusäHardness component is the essential part of already commercialized SimVaC™ expert system that optimizes selection time of a carburizing cycle for broad range of parts and materials. The present computer program substantially reduces and simplifies designing process time. Commercial users that utilize SimVaCPlusäHardness program report significant improvement of the furnace time available for production and fewer errors in the first time run heat-treat runs.
This paper will describe improvements in process controls for vacuum carburizing.
