Metallic housing of electronic device and manufacturing method thereof

A metallic housing, comprising a metallic outer frame and an inner structural member, wherein the metallic outer frame is substantially rectangular and comprises an inner surface and a plurality of latching portions protruding from the inner surface inwardly, and a plurality of latching grooves each formed between two adjacent latching portion;

• the inner structural member is made from metal-alloy and embedded in the inner surface of the outer frame by die-casting;
• the inner structural member comprises a peripheral sidewall, a plurality of matching portions, and a plurality of engaging portions protruding from the peripheral sidewall outwardly;
• the plurality of engaging portions are spaced from each other;
• the plurality of engaging portions and the plurality of matching portions protrude from the peripheral sidewall outwardly;
• each latching portion comprises at least two parallel latching ribs, and forms a receiving groove between two adjacent latching ribs, the at least two latching ribs align and extend along an extending direction of the metallic outer frame, the at least two latching ribs transverse a corner of the metallic outer frame;
• the plurality of engaging portions are respectively embedded in the plurality of receiving grooves, and the plurality of matching portions extends along a direction perpendicular to the extending direction of the metallic outer frame, and are respectively embedded in the plurality of latching grooves on two opposite sides of the receiving groove.