Cold Cracking

Cold cracks occur when hydrogen can no longer escape from the weld metal and the structure is hard and stressed. The hydrogen usually comes from damp electrodes or contamination. The risk is especially high when the part cools quickly after welding and stresses build up. To avoid this, use dry filler materials, keep an eye on heat input, and don't let the weld cool too quickly. For critical steels, it helps to keep the weld warm after welding or perform heat treatment.