gotta love the internet! omg there is a patent (applied) for this....
A filler-metal weld rod of a filler-metal composition is prepared by providing a mass of metallic powders, mixing the metallic powders with a temporary thermoplastic binder to form an injection-moldable mixture, and thereafter injection molding the injection-moldable mixture at an injection-molding temperature above the thermoplastic temperature of the thermoplastic binder to form an injection-molded rod. Any excess thermoplastic binder is removed from the injection-molded rod, and the injection-molded rod is thereafter sintered to form a filler-metal weld rod, with the temporary thermoplastic binder removed in the step of sintering.
I don't think that is actually the same thing as "Hipping"
Here is the link if you want to read it all:
http://www.freepatentsonline.com/20060024190.htmlshows how little I know...I always figured most fillers where "drawn" not cast.