As a common manufacturing process, plastic injection molding
has been widely used to fabricate a variety of products. During a
plastic injection molding cycle, the plastic part and the mold must
be cooled to room temperature so that the molded part can be solidified
and with its shape maintained. A substantial portion of the
total molding cycle could be required for
cooling. To improve the efficiency, cooling channels are usually integrated
into the mold. In general, conventional cooling channels in
simple shapes are fabricated by drilling straight-line holes. These
usually lead to non-uniform mold cooling. Without attaining
the uniformity of surface temperature in a mold, the quality