The alloy layer of tinplate is an intermetallic compound formed between base plate and tin coating through thermodiffusion during the treatment of heating and fusing after electrotinning.

镀锡板合层是镀锡后在加热熔融处理程中通热扩散在基板与锡层之间生成的一种属间化合物,因此,合层的生成与原板和镀层都有很大关系。