Cold-rolled steel is a type of steel that is processed at room temperature, using a series of rolling processes to achieve the desired thickness, flatness, and surface finish. Unlike hot-rolled steel, which is produced at high temperatures, cold-rolled steel is rolled at or near room temperature, which makes it stronger, more durable, and less likely to warp or bend.

Cold-rolled steel is made from hot-rolled steel, which is produced by heating a large slab of steel to high temperatures and then passing it through a series of rolling mills to reduce its thickness and shape it into the desired form. The resulting hot-rolled steel has a rough, uneven surface and can be prone to warping and bending due to residual stresses in the material.

To produce cold rolled steel, the hot rolled steel is first pickled to remove any scale or oxide buildup on the surface. Pickling involves immersing the steel in a bath of acid or other chemical solution, which removes the surface layer of impurities and creates a clean, smooth surface.

Once the steel has been pickled, it is then cold rolled through a series of rolling mills, which gradually reduce its thickness and shape it into the desired form. The rolling process is done at or near room temperature, which results in a more uniform, consistent thickness, and a smoother, more even surface finish.

Cold-rolled steel can be further processed and finished in a variety of ways, depending on its intended use. It can be annealed, which involves heating the steel to a high temperature and then allowing it to cool slowly, to improve its ductility and toughness. It can also be galvanized, and coated with a layer of zinc to protect it from rust and corrosion.

Cold-rolled steel is used in a wide range of applications, from automotive and aerospace parts to construction materials and consumer products. Its strength, durability, and versatility make it a popular choice for many different types of manufacturing and fabrication processes.