Analisis Variasi Tekanan Gas Las OAW Terhadap Sifat Mekanik Dan STruktur Mikro Alumunium Alloy Seri 2000 Untuk Perbaikan Komponen Enggine

Abstract

ABSTRACT

Aluminum welding technology used today can repair engine components. Welding is still often found welding defects, problems that are often faced are differences in melting point, expansion coefficient, physical and mechanical properties. So a study was conducted to determine the effect of variations in gas pressure of aluminum series 2000 on its mechanical and physical properties. This research method uses experimental, OAW welding variations in gas pressure of 50 KPa: 50 KPa, 60 KPa: 60 KPa, and 70 KPa: 70 KPa. The results of this study indicate that gas pressure affects tensile strength, hardness, and microstructure. The highest tensile strength is 107.35 MPa with a strain of 0.031% and an elastic modulus of 3,465.37 N / mm2 at a gas pressure of 70 KPa: 70 KPa, this is because the difference in gas pressure produces different heat input and distribution in each specimen. The hardness test results showed that specimens with gas pressure variations of 70 KPa: 70 KPa had the highest hardness levels in both the weld area, HAZ, and parent metal, coMPared to gas pressure specimens of 50 KPa: 50 KPa and 60 KPa: 60 KPa, this is because the greater the welding gas pressure will increase the hardness strength. Microstructure tests showed differences in the grain shape of the 2000 series aluminum alloy microstructure, the greater the gas pressure, the higher the heat received by the grains, so that the grain structure in the aluminum area expands more and the distance between the grains becomes looser.

Keywords: aluminum welding, gas pressure, OAW