According to GB/T 2520-2017 "Cold-rolled tin-plated steel sheet and steel strip" and GB/T 24180-2020 "Cold-rolled electrochrome-plated steel sheet and steel strip", tinplate can be divided into primary cold rolling and secondary cold rolling according to the cold rolling production method. Cold-rolled, among which the double cold-reduced (Double cold-reduced, "DR material") product is a second cold-rolled after the first cold-rolled annealing, so compared with the first-time cold-rolled product, it has a thinner thickness , Higher hardness and strength (see Table 1), widely used in tinplate can lid thinning.
