What is one method by which wrought iron is produced?

Wrought iron is produced through processes that involve working with the material while it is in a malleable state, typically achieved by heating it. One of the key methods of producing wrought iron is by hammering or rolling it while hot. This process not only shapes the iron but also refines its grain structure, resulting in a material that is strong yet ductile. The movement of the iron under mechanical force allows for the removal of slag (impurities) and helps achieve the desired properties in the final product.

In contrast, casting under high pressure involves forming materials in a liquid state, which does not apply to wrought iron, as this method is more appropriate for materials like non-ferrous metals. Cooling in liquid nitrogen typically relates to processes that involve extreme temperature changes for certain metals and alloys, which is irrelevant to wrought iron production. Lastly, pouring molten iron into molds describes a casting method, which produces cast iron rather than wrought iron, since cast iron is characterized by its higher carbon content and brittleness compared to wrought iron’s malleable nature.