Analisa Perubahan Nilai Kekerasan Baja ST42 Pada Proses Pack Carburizing Melalui Penambahan Arang Cangkang Sawit dan Katalisator Kerang Kepah (Polymesoda Erosa)

Abstract

ST42 steel is a Low carbon steel which has a carbon composition below 0.25%, included in the low carbon steel category. Due to the low carbon content, hardening cannot be carried out to improve its mechanical properties. One of the approaches used involves adding carbon to the steel through a carburizing process. The carburizing process aims to harden the steel surface by adding carbon to the surface of the material. The process of adding carbon is carried out using the pack carburizing method where the composition of the carbon and the catalyst and the variation temperature have been determined. The activated carbon used in this process is charcoal from palm shells and the catalyst used is shells with a ratio of 60-40%, 70-30%, 80-20%, and 90-10%. The pack carburizing process uses a temperature of 900ËšC and 950ËšC with a holding time of 60 minutes and rapid cooling using water (quenching). From the results of this study it can be concluded that each variation in composition and temperature variation has implications for the hardness value of ST42 steel after going through the pack carburizing process. The results of the analysis using the two-way ANOVA statistical method show that the effect of compositional variation has the highest contribution, which is equal to 50.59%. The highest hardness was recorded in the composition with a carbon-catalyst ratio of 90:10%, at a temperature of 950ËšC had a hardness of 819.7 HV.