Estudo avaliativo da resistência ao impacto de um aço ASTM A131 submetido a tratamento termoquímico

Abstract

With increasing development of maritime transport in Brazil, there is a need for investment in new technologies. The steel ASTM A131 is applied to the outer casing and structure of the vessels. This work is a study on the toughness of ASTM A131 steel, after undergoing thermochemical treatments carburizing, hardening and heat treatment powders (quenching and tempering) with fixed temperature and variable time. For experimental analysis, 12 were prepared test samples for testing impact with the dimensions defined by the international standard ASTM E23-94 and 05 samples approximately 30 mm long by 20 mm wide and 10 mm thick for testing hardness and metallography. The results obtained by these methods showed that the condition (02 carburizing at 950 ° C for 4 hours, tempering at 850 ° C for 30 minutes and tempering at 450 ° C for 15 minutes) showed the lowest value in testing the tenacity and the highest hardness test, and present in its microstructure formation of pearlitic grains, thus confirming the increased hardness of the material.