Chopped-fibers with axial property gradient for molded parts

摘要

A portable computing device includes a processor, a memory, and a portable computing device case that encloses one or more integrated circuits, including at least the processor and the memory. The case includes a molded fiber-reinforced polymer (FRP) material that includes a polymer material and elongated fibers that adhere to the polymer material and that have a property that varies over a length of the fibers along an elongation axis of the fibers, wherein an adhesion strength between the fibers and the polymer is determined at least in part by a property of the fibers that varies over a length of the fibers along the elongation axis.

主权项

1. A portable computing device, comprising: a processor; a memory; a portable computing device case enclosing one or more integrated circuits including at least the processor and the memory, wherein the case includes a molded fiber-reinforced polymer (FRP) material that includes a polymer material and elongated fibers that adhere to the polymer material and that have a surface roughness that varies over a length of the fibers along an elongation axis of the fibers, wherein an adhesion strength between the fibers and the polymer is determined at least in part by the surface roughness; and wherein the surface roughness that varies over the length of the fibers varies such that the surface of the fibers is locally rougher than the surface of the fibers at the ends of the fibers such that the adhesion strength between the fibers and the polymer is be stronger at the central portion of the fibers than at the ends of the fibers.