The objective of this present research program has been to investigate the factors that control the toughness of low heat input gas metal arc welds deposited using a mechanized process. This research program has studied the fracture behavior of a series of mechanized gas metal arc welds made by the CRC process. A total of five wires were used and a sixth experimental wire included for comparison purposes. The wires were chosen to represent the effect of increasing alloy content. From each weld wet chemical analyses were taken together with oxygen and nitrogen analyses.