Socially, there's a surplus of stainless steel. Depending on the duration of the surplus and storage quality, there are generally two scenarios:

1. Inventory is not aged for long and is well-stored. The processing unit retains the original quality certificate or a copy, and there are complete and clear markings on the steel or packaging. Identification of this stainless steel sheet is simply done by checking the markings on the steel or packaging against the quality certificate.

2. Long storage time, imperfect storage conditions, lack of quality certificates, and faint or missing markings on steel or packaging.

For material identification of such stainless steel sheets, it primarily involves in-depth investigation and reviewing the original documents from the processing unit. Standard invoices and other original documents are marked with the steel number. If there is no record of the steel number, local price data at that time needs to be consulted to determine the steel number through the price, which is a relatively effective method but often prone to deception. Therefore, it is essential to master the identification methods for the actual materials.