Pengaruh Post Weld Heat Treatment (Pwktur Mikrht) Terhadap Struo dan Sifat Mekanik Pegas Daun Yang Dilas Dengan Pengelasan Smaw

Carbon steel medium with carbon elements (C 0.593%) is one material is widely used in the automotive industry. One of them is the material in the leaf springs. In its function the leaf springs receive dynamic loads (which is repetitive) which is quite large and suffers from fatigue that arises after the component has funtioned. In this study SMAW welding was carried out on medium carbon steel with electrode type (E6013). PWHT is done with various variations of temperature of 700°C, 750°C, and 800°C for 30 minutes then cooled with free air. Then the composition test, hardness test, impact test and microstructure observation are conducted. The results of this study indicate that leaf spring steel is medium carbon steel with carbon content (C 0.593%). The highest hardness value at 800°C is in the weld area 189,5 HV, the HAZ area is 356,5 HV and the parent metal area is 373,5 HV, and the lowest hardness value at temperature 700°C is in the weld area 217 HV, the HAZ area 318 HV and the area parent metal 296 HV. Microstructure photo results for specimens without welding in the form of martensite + ferrite, for specimens that area only welded in the parent metal region of martensite + ferrite, HAZ martensite + ferrite areas and in the pearlite + ferrite weld area. While the microstructure of specimens that are welded and treated with post weld heat treatment (PWHT), at a temperature of 700°C has the same microstructure photo as the specimens that are only welded, while at temperatures of 700°C and 800°C also has a photo of the same microstructure that is in the metal region main pearlite, HAZ pearlite area, and pearlite + ferrite weld area. PWHT temperature which has good mechanical properties from three temperature variations is a temperature of 750°C indicated from the results of high impact prices