Preparation method for multilayer dissimilar metal composite ultra-thin strip

The invention provides a preparation method for a multilayer dissimilar metal composite ultra-thin strip. The preparation method includes the process steps that (1) different metal materials are synchronously cold-rolled for first thinning; (2) metal thin strips are polished and cleaned; (3) the upper surfaces and lower surfaces of two or more metal thin strips are closely attached; (4) two-roll synchronous cold rolling is conducted on dissimilar metal combined strips; (5) the upper surfaces and lower surfaces of 2-10 dissimilar metal thin strips subjected to preliminary combination are closely attached and then the procedures of the step (1) to the step (4) are repeated 2-10 times; (6) reversible four-roll synchronous cold rolling is conducted on a multilayer dissimilar metal composite thin strip; and (7) reversible four-roll asynchronous cold rolling is conducted on the multilayer dissimilar metal composite thin strip, and the multilayer dissimilar metal composite ultra-thin strip with the thickness being 0.01 mm-0.02 mm is obtained. According to the method, the selection range of the metal materials is wide, the requirement for equipment capacity is low, and the surface quality of the ultra-thin strip can be improved remarkably; besides, production resources are saved, production cost is reduced, and the method is suitable for large-scale industrial production.