Welding Cast Iron Cracks. While welding a cast iron be careful with it because of its carbon content. Yes if the weld cools to quickly it can cause the metal to crack.
Can Cast Iron Crack When Welded. Most welding done on cast iron is to repair cracks. Therefore it is crucial to preheat and elongate the cooldown phase.
Heat always has a deforming effect on metal and if one part of the metal heats or cools faster than another stress and cracking occur in the cast iron or weld.
Cast iron can be challenging to weld because of the materials properties. The material is very stiff and prone to heat cracking. To weld cast iron stick welding is the preferred method and you dont need any Oxy acetylene torch for it. A common material used for engine components is cast iron.