Patent ID: 6319437
Filing Date: 2001-11-20
Classification: A63B,B22F,C22C

Abstract:
A powder injection and infiltration process comprising the steps of:A) making a sintered pail comprising interconnected voids, the steps for making said sintered part comprising:i) mixing powder of a first skeleton material with a composite binder comprised of at least two binder materials to form a first mold mixture,ii) molding the mold mixture into a desired shape in a mold device to produce a first molded part,iii) sintering the first molded part to produce said sintered part, andiv) removing the composite binder to produce interconnected voids in said sintered part,B) making a heavy part comprising interconnected voids, the steps for making said heavy part comprising:i) mixing powder of a second skeleton material with a composite binder comprised of at least two binder materials to form a second mold mixture, wherein said second skeleton material is heavier in relation to said first skeleton material,ii) molding the mold mixture into a desired shape in a mold device to produce said heavy part, andiii) removing the composite binder to produce interconnected voids in said heavy part,C) inserting said sintered part and said heavy part into a mold cavity, andD) molding around said sintered part and said heavy part, said steps for said molding comprising:i) mixing powder of a third skeleton material with a composite binder comprised of at least two binder materials to form third mold mixture, wherein said second skeleton material is heavier in relation to said third skeleton material,ii) molding said third mold mixture into a desired shape by inserting said third mold mixture into a mold device comprising said mold cavity to produce a final molded part comprising said third mold mixture, said sintered part and said heavy part,iii) removing the composite binder in said third mold mixture to produce interconnected voids in said third mold mixture, andiv) at least substantially filling the interconnected voids in said final molded part with an infiltrant comprised of an infiltrant material having a relatively low melting point to produce a composite molded part.