Common steel products are hot rolled steel and cold pressed steel. In general, mechanical properties of hot rolling are better than that of cold rolling. After heat treatment, steel's tensile, yield strength, plasticity and toughness will be improved. Moreover, what's the important is that it can eliminate the residual stress while cold rolling may cause deformation because of the uneven yield of steel in the processing, which will produce residual stress. This residual stress exerts great influence on the stability. So, what are the advantages of hot rolled steel and cold pressed steel?
1. Advantages of hot-rolled steel
Hot rolled steel can destroy the cast structure of steel ingot, refine the grain of steel, and eliminate the defects of microstructure, so as to improve the microstructure and mechanical properties of steel. This improvement is mainly reflected in the rolling direction, so that the steel is no longer isotropic to a certain extent; Bubbles, cracks and looseness formed during pouring can also be welded under high temperature and pressure.
2. Advantages of cold-pressed steel
cold pressed steel refers to various types of steel fabricated by steel plate or strip through cold processing such as cold drawing, bending and pinching out at normal temperature. Its advantages are fast forming speed, high yield, and no damage to the coating. It can be made into a variety of cross section forms in order to meet the needs of the use conditions; Cold rolling can produce a lot of plastic deformation of steel, thus increasing the yield point of steel.