Külmvaltsimist

Külmvaltsimine is a metalworking process used to shape metal at or near room temperature. Unlike hot rolling, which involves heating the metal to high temperatures, cold rolling deforms the metal without significant heat generation. This process typically involves passing metal stock, such as steel or aluminum, through a series of rollers. The gap between the rollers is progressively reduced, causing the metal to become thinner and longer with each pass.

The primary advantage of cold rolling is the improved surface finish and dimensional accuracy it imparts to the material. The absence of high temperatures prevents the formation of scale, a rough oxide layer that often occurs during hot rolling. This results in a smoother, cleaner surface that is often ready for further processing or application without additional finishing steps. Furthermore, cold rolling can increase the strength and hardness of the metal through a process called work hardening or strain hardening. This occurs as the metal's grain structure is deformed and elongated, making it more resistant to further deformation.

Cold rolled products are often used in applications where precise dimensions and a superior surface finish are critical, such as in automotive parts, appliances, and precision engineering components. The process is also used to produce thinner gauges of metal that may not be achievable through hot rolling. However, cold rolling requires more force than hot rolling due to the increased resistance of the colder metal, and it can be more challenging to deform highly ductile materials without fracturing.