Dissimilar lap joint between aluminum 6061 and brass is performed by using friction stir welding (FSW) method where universal milling machine is used to implement this method. The parameters that use in welding are probe design with a varied length of pin probe 11.0 mm, 11.5 mm and 12.0 mm at 2000 rpm rotation of machine and feedrate 10 mm min−1. The macrostructure result of pin probe length 11.0 mm better than of pin probe 11.5 mm and 12.0 mm. The mechanical properties results with a pin probe length 11.5 mm a higher mean hardness value of 104.26 VHN than a pin probe length 11.0 mm and 12.0 mm with hardness values of 98.93 VHN and 70.43 VHN. Shear stress result of 67.32 MPa with a pin probe length 12 mm, better than of pin probe length 11.0 mm and 11.5 mm shear values of 40.2 MPa and 42.14 MPa.

The lap joint will be used on aluminum 6061 and 10 mm thick brass with the Friction Stir Welding method. The probe used is EMS 45 steel with variations in pin lengths of 11 mm, 11.5 mm and 12 mm. The results of this study are in length 11.5 mm with the highest Vickers hardness value of 104.26 VHn compared to 11 mm and 12 mm pin length is 98.93 VHn and 70.43 VHn. The results of shear stress are 67.32 MPa at 12 mm pin length, higher than the 11 mm and 11.5 mm pin lengths of 40.2 MPa and 42.14 MPa.