1.Overview of cold rolling process
Cold-rolled stainless steel coil is a stainless steel product processed by cold rolling process. Cold rolling is the rolling of stainless steel slabs at room temperature. This process can achieve higher dimensional accuracy and better surface quality than hot rolling. In the process of cold rolling, the stainless steel slab is rolled through multiple passes, and the roll exerts pressure on it, so that the sheet is gradually thinned, and the internal grain structure is further refined, thus improving the performance of the material.
2.Performance characteristics
(1) High-precision dimensions
Cold-rolled stainless steel coils have precise thickness and width tolerances. Its thickness uniformity is excellent, which is critical in applications where tight size control is required. For example, in the manufacture of precision parts of electronic equipment, accurate thickness can ensure the assembly accuracy of parts and ensure the normal operation of equipment. In terms of width, it can also meet the needs of different customers and industries for specific sizes, reducing the amount of cutting and adjustment work in subsequent processing.
(2) Excellent surface quality
Smooth and flat
The cold rolling process makes the surface of the stainless steel coil smooth as a mirror, and there is almost no surface roughness and oxide scale problems that may occur in the hot rolling process. This smooth surface has great advantages in some areas with high appearance requirements, such as architectural decoration and household appliance panel manufacturing. It can be used directly or just a simple surface treatment, can present a high-grade, beautiful visual effect.
Low roughness
The surface roughness of cold-rolled stainless steel rolls is very low, which is not only conducive to improving its corrosion resistance, because the rough surface is more likely to accumulate dirt and moisture, thus accelerating the corrosion process, but also in some applications that need to be closely fitted with other materials, such as the stainless steel parts in food packaging equipment and plastic seals, low roughness can ensure good sealing.
(3) Excellent mechanical properties
High strength
After cold rolling, the strength of stainless steel coil is significantly improved. The increase of yield strength and tensile strength makes the material not easy to deform when it is subjected to large external forces. In automotive manufacturing, parts made of cold-rolled stainless steel coils are better able to withstand vibration and shock during driving, improving the overall safety and reliability of the vehicle.
Good work hardening properties
Cold-rolled stainless steel coil shows good work hardening during processing. This means that in further stamping, bending and other processing operations, the material will become harder as the degree of deformation increases, thereby improving the strength and hardness of the machined part. This feature is widely used in the processing of hardware products, such as the production of high-strength stainless steel screws, nuts and so on.
3.Chemical composition and corrosion resistance
The chemical composition of cold-rolled stainless steel coils determines their corrosion resistance. Common stainless steel types such as 304, 316, etc., have their own alloying element ratio. 304 stainless steel, for example, contains about 18% chromium (Cr) and 8% nickel (Ni). The chromium element forms a dense chromium oxide protective film on the surface of the stainless steel, preventing the intrusion of corrosive media such as oxygen and water. The nickel element further enhances the stability of the protective film and improves the resistance of the material in a variety of corrosive environments, including general atmospheric environments, freshwater environments and some weakly acidic environments. 316 stainless steel also adds molybdenum (Mo) on this basis, so that it has better corrosion resistance in the environment containing chloride ions and other highly corrosive media (such as Marine environment, chemical environment).
4. Application field
(1) Building decoration industry
In the field of construction, cold-rolled stainless steel coils are widely used in curtain walls, interior decoration panels, stair railings and so on. Cold-rolled stainless steel rolls for the curtain wall create a simple, modern look, and maintain long-term shine and stability against wind and rain and air pollution. In interior decoration, it can be processed into a variety of patterns and shapes of decorative panels to meet the needs of different design styles, adding high-grade texture to the interior space.
(2) Electronic and electrical industries
Many of the enclosures and internal structural parts of electronic equipment are made of cold-rolled stainless steel coils. Its high-precision size and good electrical conductivity and corrosion resistance enable electronic components to be installed and operated stably. In the field of home appliances, such as the shell of refrigerators, washing machines, microwave ovens, etc., cold-rolled stainless steel rolls are not only beautiful and durable, but also easy to clean, which meets the requirements of modern families for home appliances.
(3) The automobile industry
Cold-rolled stainless steel coils are used in the exhaust system and body structure parts of the car. In the exhaust system, the stainless steel coil can withstand the corrosion and erosion of high temperature exhaust gas to ensure the long-term stable operation of the exhaust system. The use of cold-rolled stainless steel coil can reduce the weight of the body, improve the strength and anti-collision performance of the body, and improve the safety and fuel economy of the car.
(4) Food processing and packaging industry
Conveyor belts, storage containers, etc., in food processing equipment, and stainless steel materials for food packaging, many are made of cold-rolled stainless steel rolls. Its excellent hygiene performance and corrosion resistance ensure the safety and health of food during processing and packaging, and will not produce harmful substances or be contaminated due to contact between materials and food.
