Experimental Studies On Gtaw Gmaw And Lbw Welding Of Corten Steel

Abstract

ASTM Corten A588 grade steel is a high strength low alloy (HSLA) structural steel which is highly resistant to corrosion and has better mechanical properties than the conventional steels. Need for painting can be eliminated in Corten A588 grade steel since it forms a stable rusty layer (patina) on the top surface. Corten A588 grade steels are used in applications like the construction of a bridge, Architectural, Industrial, Shipping, Railway sector etc because of their high-strength and resistance to corrosion. newline newline newlineWhen Corten A588 steel is welded for making large structures like bridges, roofs, rail wagons, chimneys etc, and the welding process leads to a reduction in mechanical, metallurgical and corrosion property. The alternate wet/dry cycles are required for the adherent patina a protective tight stable oxide layer to form on the top surface which protects the layer beneath. But when being exposed to continuously wet or damp condition, the corrosion rate of Corten A588 grade steel increases and damaged the structure. In most of the weld structures, corrosion starts at the weld zone (WZ) and the heat-affected zone (HAZ). This is due to the metallurgical change caused by the excessive heat during the welding process. newline newline newlineTo overcome these issues related to welding, a detailed investigation is carried out on chemical composition, mechanical, metallurgical and corrosion properties of ASTM Corten A588 grade steel base metal (BM) and weldments is carried out. A novel tri- sandwich Cu-Ni-Cr coated Corten A588 grade steel solid filler - New newline newline newline newlineFiller Gas Tungsten Arc Welding (NFGTAW) for welding by three- stage electro deposition technique is prepared. Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) weldments using AWS ER70S-6 solid filler have been fabricated. Laser Beam Welding (LBW) and Autogenous Gas Tungsten Arc Welding (AGTAW) weldments have been prepared. New Filler Gas Tungsten Arc Welding (NFGTAW) weldment with improved corrosion resistance property for welding ASTM