Smidesjärn

Smidesjärn, also known as wrought iron, is a form of iron characterized by its fibrous or silky texture and the presence of slag inclusions. Historically, it was the primary form of iron used for manufacturing before the advent of modern steelmaking processes. Smidesjärn is produced by heating iron ore in a bloomery furnace, which reduces the iron oxides to a spongy mass of iron mixed with slag. This mass, called a bloom, is then repeatedly heated and hammered to expel the slag and consolidate the iron. The hammering process aligns the slag into long, thin threads, giving smidesjärn its distinctive fibrous structure.

The properties of smidesjärn make it highly malleable and ductile, meaning it can be easily shaped and worked when hot. It is also resistant to corrosion, which contributed to its widespread use in decorative and functional applications such as gates, railings, furniture, and tools. While pure iron is soft, the small amounts of slag present in smidesjärn contribute to its strength and toughness. However, it has a relatively low carbon content, which prevents it from being hardened by heat treatment in the same way as steel. Production of smidesjärn was a labor-intensive process, and its widespread use declined with the development of more efficient and cost-effective methods for producing steel, which offered superior strength and versatility. Today, smidesjärn is primarily used for artistic and decorative purposes, or in historical reproductions.