A self-regulated proportional - integral - derivative (PID) system and manual adjustment procedures were developed to control the processing temperature of the friction extrusion process. The system has been proven capable of maintaining a designated processing temperature ranges from 0.6 to 0.95 of the melting temperature of the billet material, e.g. aluminum alloys. It is also capable of adjusting the processing temperature during the process that produces a product with unique continuous gradient properties. The temperature control system can largely improve the stability of the friction extrusion process and the consistency of the quality of the product.