SIFAT MEKANIS DAN STRUKTUR MIKRO PADA SAMBUNGAN LAS GESEK BAJA SCM415H UNTUK APLIKASI POROS RODA BELAKANG MOBILThis research aims to evaluate the mechanical properties and microstructure of steel alloy SCM415H processed by friction welding for rear axle shaft application. Friction welding is a process to connect materials without using fillers and has a good quality of joint strength. Two different pressures of friction welding for 2.5 and 6 MPa were applied in this research. In addition, the initial condition of non-welded in SCM415H material was also investigated. In order to evaluate the mechanical properties, several mechanical tests i.e. Vickers hardness, tensile, torque and ultrasonic test were carried out. The result of this research is better welding connection is obtained on the final pressure of 6 MPa. The Vickers hardness is 390 HV was obtained on the welding connection area. Furthermore, the result proved that the higher pressure will affect the higher strength in the welding connection interface. The result of this research is confirmed the welding connection was not easily broken. Therefore, this research has an important role to determine the pressure applied to the friction welding.