CABURIZATION PARMETRIC EFFECT ON HARDNESS OF MILD STEEL DRILL BIT USING SUGAR CANE TRASH
Abstract
Efforts are variously being made to improve the surface hardness of mild steel from locally sourced ingredients. This research investigates the suitability of using pulverised sugar cane trash and hardwood charcoal for carburizing 0.18% carbon mild steel drill bit in order to optimize the carburizing parameters in the pack carburizing hardening process. Dynamic hardness testing machine was used to determine the surface hardness values of the carburised and un-carburized test samples. Micro structure examination was performed using standard metallographic techniques. Response surface methodology was employed on the user defined design to achieve optimization of hardness values. Varied parameters are carburization temperature (900o, 920o and 940o), premix composition of pulverised sugar cane trash and hardwood charcoal (15-85wt%, 20-80wt%,25-75wt%) and soaking time (15,30,45 and 60minutes). Adequacy measures were all in logical agreement according to the analysis of variance (ANOVA).The result showed that the premix composition of 82.5wt% charcoal and 17.5wt% sugar cane trash has the highest hardness values of 305BHN on the carburization temperature of 930oC and soaking time of 58.5minutes as obtained from the optimization process as compared with the un-carburised mild steel drill bit surface hardness of 187BHN. The present research has establish the capability of sugar cane trash as an alternative of energizing material for carburising of mild steel drill bit.
