Preliminary investigation into temperature-hardness relationship in low-carbon steel after pack carburizing.

Pack carburizing is an old method of case hardening of steel, mainly low carbon steel. In this, the sample is placed inside the solid environment of carbon/charcoal. As soon as the temperature of chamber is increased, the carbon diffusion rate on the surface of the sample increases. A thin layer (µm to mm) of carbon is possibly adhered on the surface and thereby the surface becomes hard. The present work deals with an experimental analysis to find the temperature vs hardness relationship after pack carburizing process applied in five different steel samples. Each sample was kept inside the carbon powder chamber and heated at certain temperature. Five different temperatures were selected for five different samples. It was found that hardness of the sample gets increased with increasing the heating temperature. By the simulation, an attempt was made to know the approximate temperature of the sample inside the carbon chamber in each case. Based on the simulation result, a relationship between case thickness (and thereby hardness of the sample) and sample temperature was established. [ABSTRACT FROM AUTHOR]