Sustainability of Metal Scrap Return toward Product Characteristic of Agriculture Utensil from Manufacturing Process Model by Forging and Quenching

Abstract

Hot forging is a heat treatment process by heating metal in heat furnace until upper crystallization temperature and it gives external forces up to deformation’s goal meet. The objective of this research is to compare and analyze scrap return following hot forging process in terms of hardness characteristic, tensile strength, and micro-structure. The cooling media types used in this study was SAE 20, SAE 40, SAE 50, SAE 90. This study successfully obtained hardening capability, optimum tensile strength and micro-structure scrap returns after hot forging and continued by quenching with the cooling media. Research methods in this study include: (a) test sample manufacture, (b) data retrieval namely chemical composition test, hardness test, tensile test and micro-structure observation. Research result shown that the highest value of hardness characteristic and tensile strength obtained from quenching type by SAE 20 with hardness rate of 53.5 HRC and tensile strength 65 kg/mm2 with dominant perlite phase compare to ferrite phase. Meanwhile, quenching process with SAE 90 resulted in hardness type of 49.6 HRC with tensile strength 53 kg/mm2, ? phase more dominant compared to pearlite phase. This study concludes that scrap returns metal after hot forging and quenching with cooling media SAE 20, SAE 40, SAE 50 and SAE 90 hardness characteristic and its tensile strength tends to fall and phase which formed ferrite phase more dominant compared pearlite phase.