# FUZZY MODELING OF TEMPERING PROCESS OF CAST STEEL

## Authors

• Pavel Kovač University of Novi Sad, Faculty of Technical Sciences, Department of Production Engineering, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia
• Borislav Savković University of Novi Sad, Faculty of Technical Sciences, Department of Production Engineering, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia
• Dražen Sarjanović Sara-Mont. Doo, Milića Rakića 7, Belgrade, Serbia

## Abstract

Tempering is a heat treatment process to achieve maximum toughness and ductility at a specified hardness and strength. It is important to develop an intelligent model for tempering process to satisfy requirement of mechanical properties with low cost. This paper presents a fuzzy model to predict Charpy-V notch toughness during tempering process of steel. The influence of processing parameters of steel casting, hot working and heat treatment on toughness of tempered steel was investigated. Fuzzy model for prediction od Charpy-V notch toughness of steel was established. In order to validate the model, it is employed to predict the tempering of EN GS-42CrMo4 steel. The calculated results show a good agreement with the experimental ones. This agreement indicates that the fuzzy logic is effective for modeling of tempering process of steels.

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