EFFECT OF WELDING CURRENT ON THE HARDNESS OF AUSTENITIC STAINLESS STEEL WELD JOINTS
1Okonji P. O., 1Utu O. G. and 2Akaluzia R. O.
1Department of Welding and Fabrication, Delta State Polytechnic, Ogwashi-Uku, Nigeria.
2Department of Metallurgical Engineering, Delta State Polytechnic, Ogwashi-Uku, Nigeria.
Corresponding Author: Okonji P. O., Email: paulogom2002@yahoo.com
Abstract
An investigation on the influence of welding current and filler metal type on the hardness of austenitic stainless steel was carried out. Austenitic stainless steel (AISI 304L) plate, 3mm thick, and ER308L (2mm) filler rod were used to prepare a butt-weld joint using a GTAW process and welding currents of 91- 95 amperes at 1 ampere interval. The hardness values were determined on Rockwell B scale using 1/16-inch steel ball. The result showed that there was no significant increase in hardness of the weld joints for all welding currents but registered a decrease as the welding current increased. Also the hardness values for all the welding currents recorded were slightly higher than but comparable to that of the base metal.