What Does Wrought Iron Mean?
Wrought iron is a type of iron that is tough, malleable, corrosion-resistant and ductile. "Wrought" means "worked," so the term literally means "worked iron." In ancient times, wrought iron was produced by hammering a metal repeatedly. Wrought iron is now mostly manufactured from cast iron in an indirect coal fired furnace. Wrought iron contains siliceous slag, which gives this metal its unique properties.
Corrosionpedia Explains Wrought Iron
Wrought iron is nearly carbon free and has a fibrous structure that allows it to be readily forged and welded. It also contains no or low carbon, which helps make it resistant to corrosion. Cast iron typically contains 2-4% carbon. The fibrous texture in wrought iron makes it highly ductile, allowing it to withstand in high tension and compression. Wrought iron becomes stronger the more it's worked.
Wrought iron can still be attacked by chemical corrosion. Corrosion attacks the metal surface both evenly and in selected areas. Attacked areas of metal can cause stress corrosion cracking and pitting. Wrought iron is mostly subject to corrosion when the unprotected metal is exposed to oxygen along with moisture. Galvanic corrosion also occurs in wrought iron when it has direct contact with copper or zinc, and to a lesser extent galvanized iron or steel.
Although wrought iron is fatigue resistant, it will deform considerably within its elastic limit. Defects in the wrought iron may lead to fracture in the structural elements.