The previous article mentioned that tinplate can be divided into two categories according to the annealing method: BA material and CA material, that is, the tin-plated original plate can be made of CA material or BA material. It is generally believed that CA tinplate is better than BA tinplate, but why do some people only want to use BA tinplate? I still have questions. Is there BA chrome plating? Let's briefly clarify the grievances between BA and CA.

From the development history, BA annealing comes first, then CA. The later the technology, the more advanced it is. So CA is indeed superior. Let's compare the advantages and disadvantages of BA and CA units:

From the macroscopic indicators after annealing, such as mechanical properties, there are certain differences:

From the perspective of microstructure, the grains of BA material are coarse because of sufficient annealing and good recovery of the grains after rolling. The grains of CA material are relatively fine because of rapid annealing and short time, which retains the influence of rolling.

Economic technical indicators such as the variable cost of annealing process, BA material should be higher than CA, because the material and energy consumption per ton of steel is relatively high. However, from the perspective of fixed costs, CA should be higher than BA, because CA has a large investment and high management costs. Therefore, in general, the difference between the two will not be too big. However, the price of BA material in the market is much lower than that of CA, which should be due to other factors.

Both tin plating and chrome plating can use BA or CA original plates, but tin plating and chrome plating are suitable for different occasions. For example, flower basket barrels prefer BA materials, and the barrel body cannot be chrome-plated. Therefore, there is no BA chrome-plated iron for this purpose, which may lead to misunderstanding.

Whether you like BA or CA, there is always a tinplate that can be used!

The Essential Guide to Metal Packaging