PENGARUH TEMPERATUR ANELING PADA PENGELASAN PER DAUN/LEAF SPRING MOBIL SP 150 TRUK DENGAN UJI MEKANIK DAN STRUKTUR MIKRO

Abstract

The problems that occur in the life spring leaf spring are corrosion or overload, the load carried is more than 15 tons, the solution is to replace or recondition the life spring leaf spring, the reconditioning does not last long, for this reason this study aims to determine the effect of annealing temperature on welded joints on the hardness of sp 150 truck steel, this steel contains a composition of 0.30% C, 0.030% P and 1.50% Mn and several other elements. The method used is an experiment by connecting the two broken metals with a welding process with an electric arc welding electrode, then Annealing heat treatment and seeing the difference in microstructure in the connection, welding and non-welded areas. By testing the same three materials but differentiated by different treatment / Annealing treatments with temperatures of 400C, 600C, and 700C with holding time of 30m, 60m, and 90m cooled with open air, resulting in different hardness, namely sample A (Avg 321), sample B (Avg 294) and sample C (Avg 189). The different microstructures of the three materials tested, it can be concluded that annealing at high temperatures can cause a decrease in strength in high carbon steel so that it is more efficient to use relatively lower temperatures.