I believe everyone has heard of the hot rolling of stainless steel plate, cold rolling refers to the cold processing of stainless steel strips into various types of steel at room temperature, after cold drawing, cold bending, cold drawing and other cold processing. They have both advantages and disadvantages, let's take a look at them in detail
I believe everyone has heard of the hot rolling of stainless steel plate, cold rolling refers to the cold processing of stainless steel strips into various types of steel at room temperature, after cold drawing, cold bending, cold drawing and other cold processing. They have both advantages and disadvantages, let's take a look at them in detail.
Advantages of hot rolling and cold rolling
1, hot rolling: the advantage of stainless steel plate hot rolling is that it can destroy the casting structure of the ingot, refine the grain of stainless steel, and clean up the defects of the microstructure, making the structure of stainless steel more dense and optimize its mechanical properties. This optimization is usually reflected in the rolling direction, so that stainless steel is no longer isotropic to a certain extent;
2, in addition, it will also make the bubbles, cracks and porosity generated during pouring under high temperature and pressure to be welded.
3, cold rolling: its advantages are fast forming speed, high yield, and will not damage the coating, can be made into a variety of cross section forms to meet the needs of the conditions of use;
4, cold rolling can make stainless steel produce great plastic deformation, thereby improving its yield point.
Disadvantages of hot rolling and cold rolling
1, hot rolling: First of all, after hot rolling, non-metallic inclusions (mainly sulfides and oxides and silicates) inside stainless steel will be pressed into sheets, resulting in the layered phenomenon of stainless steel plate. This will deteriorate the tensile properties of the stainless steel along the thickness direction and may cause interlayer tearing when the weld is contracted. The local strain induced by weld contraction often reaches several times the strain at yield point, which is much larger than the strain caused by load.
2, secondly, the uneven cooling after hot rolling will produce residual stress. The so-called residual stress is the internal self-equilibrium stress of stainless steel under the action of no external force, and there will be such residual stress in hot-rolled steel of various sections. Generally speaking, the larger the section size of steel, the greater the residual stress. Although the residual stress is self-balanced, it will have a certain impact on the performance of stainless steel components under the action of external forces. For example, it will have an adverse effect on deformation and stability.
3, cold rolling: First of all, although there is no hot plastic compression in the molding process, there is still residual stress in the section, which will definitely affect the overall and local buckling characteristics of the stainless steel plate.
4, the second is that the style of cold-rolled steel is usually an open section, so that the free torsional stiffness of the section is low. It is easy to appear torsion when bending, and easy to appear bending and torsional buckling when pressurized, and the torsional resistance is poor.
5, in addition, the wall thickness of cold-rolled steel is small, and it is not thickened at the corner of the connection of the plate, and the ability to withstand the local concentrated load is not very high.
