Influence of Weld Process Parameters on the Geometric Variability of the Gas-Metal Arc Welds

In an attempt to develop gas-metal arc-welded (GMAW) sheet steel coupons with tightly controlled weld geometry for fatigue testing, it was discovered that the very slight changes in welding process parameters strongly influence the weld geometry. The extent of fusion zone, horizontal and vertical leg lengths, and depth of penetration were considered to define the weld geometry. In order to elucidate the sensitivity of weld geometry to process parameters, a study was conducted on welding of various types of specimens. The paper reports the results of variations in weld geometry with small changes in process parameters. In addition, through several examples, it is demonstrated that variability in the weld geometry is unavoidable even with very tight weld process control.