Comparison of Heat Treatment and Mechanical Properties of Mild Steel Used in Nigeria

Abstract

The paper presents the study of carburization of two samples of mild steel from Nigerian Spanish Engineering Limited (NSE) and Top Steel Nigeria Limited (TL) in Ikorodu Lagos, there heat treatment, that consists of annealing, tempering, normalizing and hardening process and the mechanical properties. The paper was aimed at investigating the mechanical properties and the impact strength of the heat-treated mild steel samples after carburizing, the two samples undergoes carburization within a temperature range of 850-950°C, then quenching process of different quenching method. After quenching all the samples, they undergo mechanical test (Yield Strength, ultimate tensile strength and percentage elongation) using Universal Testing Machine (UTM) and impact strength. The heat treatment result shows a superior improvement on the mechanical properties of the two samples than As Received that shows more ductility toughness and strengths. From the observed result the mechanical properties of the two mild steels samples were found to be influenced by the carburization, whereby NSE present better result than TL with almost 15-20%. Conclusively, heat treatment process increases the mechanical properties of the mild steel, which gives a better construction when using the carburized mild steel.