Modeling of Austenite Grain Growth Behavior for AISI 302 Stainless Steel

Abstract

Among the metals used in foundry, we find the austenitic stainless steels, which are used in several fields because of their mechanical properties, which can change during the heat treatments; for that, it is important to understand and control the growth of the austenite grains. Modeling austenite grain growth by considering the effects of heating temperature, holding time, and initial austenite grain size on austenite grain growth. In this paper, the austenite grain growth process of AISI 302 steel was studied in a temperature range of 900 to 1000 °C and a holding time of up to 360 minutes. Based on the experimental results and a combination of Arrhenius and Sellars type equations, a mathematical model of austenite grain growth was developed. From the experimental part, it was found that the increase in heating temperature caused the dissolution of carbides; therefore, the size of austenite grains grew faster, implying a higher growth rate. The prolongation of the holding time also led to the increase in the size of the austenite grains. Based on statistical indicators and a comparison between experimental and predicted results, the ability of the model to predict austenite grain growth was confirmed.