Experimental Investigation of Tensile Strength Behavior on Friction Welded Austenitic Stainless Steel Grade 304L Joints

摘要

Solid state friction welding technique is the one of the best effective and efficient method for joining similar as well as dissimilar materials without applications of filler rod. Recently austenitic stainless steel grade 304L are used to join the similar combination in the automobile, electrical, chemical, nuclear, marine industries and defence. The main objective of this experimental investigation is to join the similar materials of size 12 mm in diameter and to find the optimum level of tensile strength. During the friction welding process, heat is generated at the interface of joining the metal under plastic deformation by converting the mechanical energy into thermal energy. The experiments were conducted by the proper selection of friction welding parameters to obtain good mechanical strength using L_9 orthogonal array recommended by the design of experiments. In this experimental investigation, austenitic stainless steel grade 304L has been welded by using the KUKA continuous drive friction welding machine with constant rotating speed of 1500 rpm in Welding Research Institute of BHEL. Joining of Similar material combination plays important role in the various applications required for finding the mechanical properties of the welded joint. The optimum welding parameters of friction welding process are great impact in the manufacturing environment. The basic friction welding parameters such as heating pressure, upset pressure and heating time were selected and examined at three different kind of levels, to study the correlation between the welding parameters and tensile strength are found in the study. The strength of the welded joints was evaluated by using the computer controlled universal testing machine. The present experimental work is focused on the optimization of friction welded process parameter using design of experiments and the most optimum level of friction welding parameter can be used for the further investigation. Results of experimental investigations indicated that upset pressure plays crucial role in the friction welding process.