Hotworked

Hotworked is a term used to describe metal that has been shaped by hot working processes, performed above the material’s recrystallization temperature. Common hot-working methods include forging, rolling, extrusion, and pressing. Working at elevated temperature allows large plastic deformations with lower flow stress, enabling the production of complex shapes and large cross-sections that would be difficult to achieve by cold forming.

Temperature and conditions vary by material but are typically above the recrystallization temperature and may range from several hundred to over a thousand degrees Celsius. For example, steel hot work often occurs around 1,000–1,200 °C or higher, while aluminum hot work is usually in the 350–500 °C range. Surface oxidation and oxide scale are common in hot processing and may require surface finishing.

Microstructure and properties typically differ from cold-worked material. Hot-worked metals generally have reduced residual stresses and enhanced ductility relative to their cold-worked counterparts but may exhibit lower strength and hardness unless subsequently heat treated. The grain structure can be elongated and non-uniform immediately after hot working, often becoming more uniform through post-processing such as annealing or normalization.

Post-processing and finishing commonly follow hot working. Heat treatments—such as annealing, normalization, solution treatment with aging, or stress relief—are used to achieve desired strength, toughness, and dimensional stability. Machining, grinding, or surface finishing may also be required to meet specifications.

Applications include large structural components, automotive and aerospace parts, and extruded or heavily formed sections where complex shapes and high productivity justify hot-working methods. See also cold working, heat treatment, recrystallization, forging, rolling.