ASTM A36 steel carburized with charcoal from saba banana (M. acuminata × balbisiana) peels and CaCO3 from chicken (G. gallus domesticus) egg shell

Abstract

In this research, ASTM A36 low-carbon steel was carburized using a mixture of charcoal and calcium carbonate (CaCO3). The charcoal made from saba banana peel (Musa acuminata x balbisiana) and the CaCO3 come from chicken eggshell (Gallus gallus domesticus). These materials are local organic waste and were chosen to improve the quality of standard low carbon steel economically. Comparison between processes using charcoal and CaCO3 ratio of 90:10, 80:20, and 70:30 has been made and analyzed. The observation focused on seeing the difference in mechanical property and metallography characteristics of said processes. Impact test shows that material toughness increases as the relative amount of carbon (in the form of charcoal) increasing in carburizing mixture. Sample 90:10 shows the highest average toughness value of 14.69 MPa, 35% higher than the toughness of 70:30 sample. Sample 70:30 has the highest hardness of 80.2 HRA, 27% more than the hardness of sample 90:10 and 68% higher compared to non-carburized steel. The metallographic analysis shows processes with higher CaCO3 ratio result in deeper diffusion of carbon. Effective transformation into martensite also achieved with increasing CaCO3 ratio.