Study of Mechanical Properties of Carbon Steel Plate SA-516 Gr. 70 Welded by SAW Using V-Shape Joint Design

Abstract

Submerged arc welding (SAW) is a fusion type welding and it isconsidered one of the most important welding types due to its inherentcapabilities of high welding speed, high deposition rate, welding largethickness plates owing to its deep penetration characteristic and manyother advantages. In this study, the goal was to investigate the effect ofwelding parameters, namely (welding current and welding speed) as wellas the joint design on the mechanical properties (yield stress, bendingforce on the face of the weldment and hardness of the weld metal.Experiments were conducted employing Design of Expert (DOE) softwareand Response Surface Methodology (RSM) technique. The experimentswere conducted by welding ASME SA-516 Gr. 70 steel plate withdimension (300 mm × 150 mm × 10 mm) depending upon the design matrixdeveloped via the DOE. Results manifested that the optimum processparameters for maximum yield stress, maximum bending force andminimum hardness were at (425 amps) welding current and (35 cm/min)welding speed, where the arc voltage was held constant at (37 volts). Theoptimum values for the yield stress, bending force and hardness were(474.447 MPa, 36.997 kN and 150 HV), respectively. Finally, it was foundthat the predicted and experimental results of yield stress, bending forceand hardness agree very well according to the ultimate error (1.05%,1.92%, and 4.25 %), respectively