Multi-response optimisation of rotary friction welding of austenite stainless steel tube joints for improved strength and corrosion resistance

This study focuses on the multi-response optimization of rotary friction welding for joining identical austenitic stainless steel tubes. The study utilized Response Surface Methodology to optimize the welding process parameters, including rotational speed, friction pressure per time, and forging pressure per time. The objective was to enhance the Tensile Strength (MPa), Notch Tensile Strength (MPa), and Impact Toughness (J) of stainless steel tube joints. The experiment was conducted using a central composite design, which involved three components and five levels. The study's findings indicated that the rotating speed was the most influential process parameter, with friction pressure/time and forging pressure/time following closely behind. The optimal process parameters for enhancing the tensile characteristics of the rotary friction welded joint are determined to be a rotating speed of 27.6 rps, a friction pressure per time of 7.13 MPa/s, and a forging pressure per time of 7.83 MPa/s The Tensile Strength, Notch Tensile Strength, and Impact Toughness achieved under optimal conditions are 619.2 MPa, 734.1 MPa, and 41.29 MPa, respectively.