A study on microstructural changes and mechanical properties in steel rods subjected to uniform and non-uniform cooling layout using a finite element analysis

Abstract

This paper presents a mathematical model for prediction of temperature history, final microstructures, and transformation kinetics in steel rods subjected to non-uniform cooling conditions. To achieve this goal, a mathematical model based on two-dimensional finite element method is developed to solve the governing heat conduction equation with non-uniform boundary conditions. The additivity rule is coupled with the finite element analysis to assess the kinetics of austenite decomposition during continuous cooling. The effect of decarburization during heating stage is also considered in the model employing Fick's second equation. To verify the predictions, time—temperature histories during cooling of a high carbon steel under different conditions have been considered and microstructural studies have also been performed by means of optical and scanning electron microscopy. The predictions have been found to be in good agreement with the experimental data.