MECHANICAL PROPERTIES OF WELDING JOINTS USING TUNGSTEN ARC WELDING (TIG) AT DIFFERENT DC CURRENT

Author(s): 

Munaf Hashim Ridha1* Ahmed Ibrahim Razooqi2 and Muammar Ibrahim Ismail3

Affiliation(s): 

1Middle Technical University, Engineering Technical College-Baghdad, Baghdad- Iraq

2Middle Technical University, Engineering Technical College-Baghdad, Baghdad- Iraq

3Middle Technical University, Baghdad Technical Institute, Baghdad- Iraq

*Corresponding Author Email: munaf.hashim@yahoo.com

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Welding is one of the important industrial methods, therefore many techniques have been developed to get an efficient and low cost welding process for different kind of materials. In this research, the mechanical properties of welded joint were implemented using (TIG Welding) to join Low carbon steel 1020 AISI, at variable DC current and constant voltage, wire filler ER70S-3 with argon productive case. Some of preparing sheet metal were subjected to shot peening by steel ball in diameter 1.25mm for half an hour before welding then to be welded at the same welding conditions. The objective of the current work is to be find optimum working conditions and parameters for welding thick low carbon steel plates. Hardness, tensile, bending, microstructure was tested. The result shows an improvement of 12% in the tensile strength of the welded joints comparing with the base metal. The tensile strength of the welded joints of the shot peening metal was 8% higher than the tensile strength of the welded metal without shot peening. The best tensile result was increased when increased the heat input due to the change in used current and the number of passes. The increasing in bending strength of the shot peening weld joints was11.15%. higher than the bending strength of the welded metal without shot peening. The hardness of the welds joint was increased for all joints because of the change in the chemical composition of the weld pool for the weld area.