Micro-structural and mechanical characterization of pulverized wood charcoal and egg-shell as organic carbon additives for grey cast iron carburization

The use of wood charcoal as activated carbon for metal carburization is increasing because of its carbon content percentage ranging from 50%-95%. Pulverized carbon from wood charcoal when dispersed into metals offers excellent compression strength which improves the wear characteristics of mild steel material. It is; therefore, important to have the knowledge of the microstructure and mechanical characterisation of activated carbon from wood charcoal for effective and efficient carburization process. In the present study, pulverized wood charcoal and eggshell were characterized using transmission electron microscope (TEM) and x-ray dispersive spectroscopy (XRD) to determine their morphologies and grain size distributions. The characterized organic carbon was further employed to carburize the grey cast iron. It was observed that graphite was deposited on the surfaces of the carburized samples at different temperature compared to as-received sample. This indicates the carbon concentrations. Also, the result of the hardness test revealed that there was increased trend of hardness distribution which is associated with carbon concentration at varying carburizing temperature. Thus, the organic carbons are great substitutes for enhancing the mechanical properties of grey cast iron.