Metal substrate with double-layer coating film

The utility model discloses a metal substrate with a double-layer coating film. The utility model relates to the field of metal substrates. Including underlying metal coating, a transverse fixing mechanism is arranged at the top of the bottom-layer metal coating; and the number of the transverse fixing mechanisms is multiple, each transverse fixing mechanism comprises a fixing block, a sliding groove is formed in the middle of each fixing block, an inner cavity of each sliding groove is slidably connected with a cambered surface sliding rod, a limiting push plate is arranged on one side of each cambered surface sliding rod, and a limiting groove is formed in the side, close to the corresponding limiting push plate, of each fixing block. According to the utility model, the transverse fixingmechanism is arranged; the arc-surface sliding rods drive the annular limiting plates to move in the inner cavities of the annular grooves in the same direction at the same time, the arc-surface sliding rods are used for dri