[Problem] To prepare a thin plate having excellent corrosion resistance, conductivity, and formability at low cost.[Solution] A thin plate is prepared by an ultraquenching transition control injector with a mixture of a metal powder having corrosion resistance to form a matrix and a powder having conductivity, as a raw material. An obtained thin plate has a conductive material component that exists, without dissolving, in a metal matrix exhibiting corrosion resistance by passivation, thereby having aforementioned characteristics.