This research aims to study the friction welding method for dissimilar metals on low-carbon ST 37 and Aluminum 6061 with galvanized pipes. Aluminum 6061 is used in certain heavy-duty applications e.g.: Truck frames, commercial bridges, and Transportation operations. Galvanized pipes are widely used in drinking water supplies in Yogyakarta, Indonesia. St 37 carbon steel is widely sold on the market, the composition is iron and a little carbon, and the application is reinforced concrete in multi-story buildings. This research uses a lathe at 860 rpm and the temperature is measured. The galvanized pipe is installed in the lathe chuck, while the aluminum pipe is installed in the tail stock, pressed into the galvanized hole, causing friction. Heat is used to make the galvanized pipe plastic and a mechanical bond will occur. Galvanized pipe material with a diameter of 1.5″, 110 mm long and 6061 aluminum bushing with a diameter of 1.5″ 30 mm long and low carbon ST 37 was used. The welding process was carried out with a lathe at a speed of 860 rpm. This research aims to determine the microstructure, Vickers hardness value, and shear force. The results of this research show that St37 low carbon steel bushings and galvanized pipes produce a temperature of 225.8 °C. The rough microstructure of stainless steel galvanized steel (Fe–Zn) is a combination of Fe–Zn and mild steel St37. This reaction forms an oxide layer turning the surface color black. Low heat energy does not affect the microstructure. The effect of heat energy has little effect on St37 steel mixed with aluminum 6061. Vickers hardness is between 225 VHn and 55.86 VHn. In aluminum 6061 bushings the highest hardness value is 140 HVn, and the highest shear force is 8.4 kN.