Performance and Characteristics of Stationary Arc and Rotating Arc-Gas Metal Arc Welded DMR 249 Naval Grade Steel Joints

Abstract

In this investigation, 12-mm thickness naval grade high-strength low-alloy steel plates were welded by rotating arc-gas metal arc welding (RA-GMAW) and stationary arc-gas metal arc welding (SA-GMAW) processes. The main objective of this work was to carry out the comparative analysis of mechanical properties and microstructural characteristics of the joints fabricated by the outlined welding processes. From this experimental work, it is found that the ultimate tensile strength, yield strength, and impact toughness of the RA-GMAW joint are 15 % higher than those of the SA-GMAW joint. This is because of the formation of a higher volume percentage of acicular ferrite microstructure and island martensite/austenite constituent in the weld metal region of the RA-GMAW joint. Moreover, from the productivity point of view, the number of passes in the RA-GMAW process was minimized to three (from six passes), and the width of the heat-affected zone was also reduced by 45 % to SA-GMAW processes. Overall, the RA-GMAW joints are found to have superior mechanical properties and microstructural characteristics compared to SA-GMAW joints.

Enhancement of the Microstructure and Mechanical Properties of 1020 Carbon Steel and AISI 304 Stainless Steel Dissimilar Weld Using Different Post-Weld Heat Treatments

“…Unlike the shielded metal arc welding (SMAW) technique, GMAW has solved the restriction of using an electrode of limited length [2]. Other unique advantages of GMAW over SMAW include better weld penetration [3], neater and cleaner weldments [4]. Currently, joining metals using friction stir and laser welding techniques has been proved to produce weldments of higher quality in terms of low HAZ, lower distortion and dilution, etc.…”