Ultra-thin stainless steel foil is cold-rolled from ordinary stainless steel with an initial thickness of 0.8 mm.
Smelting Requirements for Blank Steel: The smelting of medium-carbon stainless steel must be exceptionally pure, free from impurities such as aluminum, magnesium, oxygen, and sulfur. These undesirable elements must be completely removed before the steel can be used for rolling, making the smelting requirements for blank steel extremely stringent.
Cold Rolling Requirements: Due to the hardness of stainless steel, it cannot be stretched easily like tin or aluminum. The cold rolling process requires the use of 20 rollers to gradually elongate the material.
Roller Requirements: The rollers must be perfectly flat and smooth. Given the wide steel strip, a 180-ton hydraulic press is needed to ensure the required pressure for rolling.
Annealing During Cold Rolling: The cold rolling process thins and elongates the material. To prevent the steel from breaking during rolling, annealing is necessary to relieve the internal stress caused by the rolling process.
Cooling During Cold Rolling: The heat generated by cold rolling must be carefully managed. The cooling process is highly specific and cannot be too fast or too slow to ensure the material's integrity.
Key Challenge - Adjusting the Roller Series: A critical challenge in producing ultra-thin stainless steel foil is the constant adjustment of the roller series. For instance, producing a steel foil with a thickness of 0.02 mm requires four rolling passes, while producing a foil with a thickness of 0.015 mm requires five rolling passes. Each time the thickness is reduced, the roller settings must be recalibrated accordingly.
Production Environment: The production process requires a clean environment. Any floating particles that land on the steel strip can cause the product to be scrapped.
Surface Inspection: After each rolling pass, the surface of the steel must be inspected for color differences, flatness, and other imperfections. No scratches or visible patterns can be present on the stainless steel foil.
