Patent ID: 6810941
Filing Date: 2004-11-02
Classification: B22D

Abstract:
An injection mold for semi-solidified Fe alloy, comprising a pair of mold members defining a mold cavity, and a scalping gate for removing a surface oxide film of a semi-solidified Fe alloy as the semi-solidified Fe alloy is pressurized in a pressure chamber in one of said mold members and injected into the mold cavity, said scalping gate being arranged between said pressure clamber and a runner provided in the other of said mold member, said runner being in communication with said mold cavity, said mold members and said scalping gate each having a surface that is contacted by said semi-solidified Fe alloy during casting thereof;said mold members and said scalping gate each comprising a copper alloy having a thermal conductivity of not less than 120 W/(mÂ·K) and a hardness of not less than 180 HB; and said mold members and said scalping gate each comprising a cermet layer consisting essentially of at least one member selected from the group consisting of Co, Cu, Cr and Ni, said cermet layer being formed by electro-spark deposition at least partially on said surface, that is contacted by the semi-solidified Fe alloy, via a Ni alloy intermediate layer, said Ni alloy intermediate layer having a film thickness in a range of 5-100 &mgr;m and an arithmetic mean surface roughness Ra within a range of 5-50 &mgr;m, said Ni alloy intermediate layer being formed by electro-spark deposition.