Thin metal casing with plastic part and manufacturing method thereof

A thin metal casing with at least one plastic part comprising a thin metal casing, a TPR adhesive layer and at least one plastic part;

• wherein the thin metal casing is formed by a metal substrate with a certain thickness being processed while a plurality of micro concave holes is naturally formed on an inner surface and an outer surface of the metal substrate during manufacturing of the metal substrate and is distributed evenly thereon;
• the TPR adhesive layer is a thermoplastic rubber layer synthesized by butadiene-styrene block copolymer and hydrocarbon petroleum resin, having a thickness of 400-500 μm and arranged at the metallic inner surface of the thin metal casing;
• the plastic part is formed by plastic injection molding that sets and fixes the thin metal casing with the TPR adhesive layer into a cavity of an injection mold for injecting at least one injection material to the inner surface of the thin metal casing;
• wherein the plastic part and the TPR adhesive layer are melted and integrated with each other by injection pressure and temperature of the injection material during injection molding while a part of the thickness of the TPR adhesive layer is simultaneously infiltrated into the micro concave holes on the metallic inner surface of the thin metal casing so that the injected plastic part and the thin metal casing are connected to form an integral composite structure.