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 comprises an inner surface and a plurality of latching portions protruding from the inner surface inwardly;

• 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 and a plurality of engaging portions protruding from the peripheral sidewall outwardly;
• the plurality of engaging portions spaced from each other;
• the plurality of engaging portions is respectively embedded in the plurality of latching portions.

A manufacturing method for a metallic housing of an electronic device, the method comprising:

• (1) providing a die-casting mold comprising a male die and a female die engaging with the male die, the male die defining a pouring gate therein, and the female die defining a cavity therein corresponding to the pouring gate;
• (2) positioning a metallic outer frame in the cavity of the female die as an insert, the outer frame comprising an inner surface, a plurality of latching portions protruding from the inner surface inwardly, and a plurality of latching grooves each formed between two adjacent latching portions, each latching portion comprising at least two parallel latching ribs, and a receiving groove formed between two adjacent latching ribs;
• (3) assembling the male die to the female die to cover the cavity, thereby communicating the pouring gage with the cavity;
• (4) casting pressured molten metal-alloy into the cavity via the pouring gate to form an inner structural member embedded in an inner side of the outer frame, the inner structural member comprising a plurality of engaging portions respectively embedded in the plurality of receiving grooves, and a plurality of matching portions respectively embedded in the plurality of latching grooves;
• (5) dissembling the male die from the female die to expose the cavity;
• and
• (6) removing the outer frame and the inner structural member from the female die.