Heat-sink base provided with heat-sink fin portions, method for producing same and motor provided with same

A method for producing a heat sink, the method comprising:

• a) placing a pattern having a sublimation temperature into a chamber;
• b) filling the chamber with molding sand, thereby defining a space;
• c) melting a base material to its molten state;
• d) pouring the molten base material into the space to make the pattern sublimated;
• and
• e) cooling the base material, so that the pattern is replaced by the base material to produce the heat sink, wherein the heat sink comprises:
• (i) a heat sink member comprising a plurality of heat sink fin portions and at least one anchor portion for each of the plurality of heat sink fin portions, and (ii) a tubular base body comprising a base portion and a holder portion, the holder portion recessed into an outer surface of the tubular base body and being adapted to clamp the anchor portions.