An investigation of welded 304 and 316l stainless steel rods through rotary friction welding process

Abstract: Rotary friction welding is a solid-state method wherein one part is turned around at excessive speed and is pressed towards some other component that is held deskbound. The ensuing friction heats the elements, inflicting them to forge collectively. It is the most productive and effective welding strategy for joining similar and dissimilar round materials. In the friction welding process parameters such as friction pressure, forging pressure, friction time, forging time, and burn-off are considered to have a great impact on the quality of welded joints. Therefore, these parameters must be optimized accordingly to prevent defects such as lack of bonding occurring at the interface of the joints. Austenitic stainless steels are a category of alloys with a face-centered-cubic lattice structure and the most common types of stainless steels consist of elements such as chromium, nickel, iron, and carbon. These types are considered nonmagnetic. Type 304 austenitic stainless steel is the most utilized steel grade, hence, 316L is presumably the second most basic utilized business evaluation of hardened steel provided into various enterprises. 304 and 316L austenitic stainless steel is commonly used in nuclear power industries. In this study, continuous drive rotary friction welding has been utilized to weld similar joints (316L) and dissimilar joints of 316L to 304 austenitic stainless steel. Similar and dissimilar rods of 12.5 mm diameter were welded to investigate the effect of friction welding process parameters on the quality of joints. Rotational speed, friction pressure, and forging pressure were varied while burn-off, friction time, and forging time were kept constant, and these conditions were applied to all samples. The effect of the process parameters on the quality or strength of the welded joints was investigated by Optical microstructure (OM), Scanning electron microscope, and microhardness test. The chemical composition of the welds was analyzed by Energy Dispersive Spectroscopy (EDS). The results obtained illustrate that the variation in hardness and microstructure in the interfaces of the welded joints was due to the process parameters that were varied during the friction welding process. It was also discovered that low rotational speed and friction pressure led to a lack of bonding or voids at the interfaces of the welded joints.M.Tech. (Mechanical Engineering