It is an advantage of the present invention to provide for the ready and secure attachment of plastic items to metal items without requiring the use of an adhesive. This can be accomplished at least in part through the use of a metallic surface that is adapted to accept the flow of melted plastic into one or more surface irregularities therein, such that a plastic item can be ultrasonically bonded to a metal item having such a metallic surface.
In various embodiments of the present invention, an electronic device can include a first housing component adapted to hold or contain one or more internal electronic device components, and one or more electronic device parts formed from a plastic material and attached to the first housing component. At least a portion of the first housing component can be formed from metal. The metal portion can include a first metallic surface region having a surface roughness comprising one or more surface irregularities. The plastic part or parts can be attached to the first housing component via an ultrasonic bond, such that a portion of plastic material is formed into one or more of the surface irregularities.
This process would improve the structure of Apple devices which are already some of the most solid devices around.
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