SURFACE TREATMENT METHOD FOR MAGNESIUM ALLOYS AND MAGNESIUM ALLOY MEMBERS THUS TREATED
    4.
    发明公开
    SURFACE TREATMENT METHOD FOR MAGNESIUM ALLOYS AND MAGNESIUM ALLOY MEMBERS THUS TREATED 审中-公开
    镁合金表面处理方法,并根据所处理的零件镁合金

    公开(公告)号:EP1274881A1

    公开(公告)日:2003-01-15

    申请号:EP01922818.8

    申请日:2001-03-29

    IPC分类号: C23C22/78

    摘要: The present invention provides a surface treatment method for magnesium alloys that can form a uniform, fine, and dense conversion coating on a magnesium alloy surface on which mold release agent, an oxide layer, and an alloying component (e.g., aluminum and zinc) segregation layer are potentially present, and also provides magnesium alloy members whose surface has been treated by the aforesaid surface treatment method. The surface treatment method of the present invention comprises a degreasing process to degrease the surface of the magnesium alloy, a chemically etching process to chemically etch the alloy, and a conversion treatment process to form a conversion coating. The chemical etching forms a magnesium phosphate coating having a coating weight of 10 to 2,000 mg/m2, measured as phosphorus, by bringing the surface of the magnesium alloy into contact with an aqueous solution containing a phosphoric acid-type compound.