Steel is the most popular metal used in industries and daily life. However, few people are aware that certain steel varieties can be sold at prices even higher than that of gold.
About five years ago, broadsheet super-thin stainless steel foil with thickness of less than 0.02 millimeters was sold in China at several hundred yuan per gram depending on its actual thickness, while the price of gold was less than 300 yuan ($46).
This is because the Chinese market for such products was not as strong as overseas suppliers. In 2016, to break the monopoly of foreign suppliers, China began research and development into broadsheet super-thin stainless steel foil. With a thickness of 0.02 mm, or one-third of the diameter of a human hair, the product can be easily torn apart by hand. As a result, it is called "hand-torn steel.The steel foil sheet is made this thin to meet special requirements in specific industries. Generally speaking, the product is meant to take the place of aluminum foil in similar industrial applications, like in the fields of aerospace, electronics, petrochemicals and automobiles.Compared with aluminum foil, the super-thin stainless steel foil performs better in resistance to erosion, moisture and heat.
According to the engineer, only steel sheet thinner than 0.05 mm can be called steel foil.Most of the steel foil products made in China are more than 0.038 mm in thickness. China now is among the few companies in the world capable of producing soft stainless steel foil of 0.02 mm.
After more than 700 experiments and trials over two years since 2016 we successfully developed the product in 2018, In the manufacturing process, 24 pressings are required for the 0.02-mm-thick and 600-mm-wide steel sheet.
In China hand-torn steel is currently sold at less than 10 yuan a gram. The price represents dramatically lower purchasing costs for buyers compared with several years ago.We are now producing an even thinner steel foil with a diameter of 0.015 mm, which is used in the production of batteries for electric vehicles.