PRETREATMENT METHOD FOR MAGNESIUM ALLOY MEMBER

• Main Authors: NISHINO NAOHISA, KANEKO TADATAKA
• Format: Patent
• Language: English
• Published: 03.07.2003
• Edition: 7
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE

PROBLEM TO BE SOLVED: To provide a pretreatment method for a magnesium alloy member, which is simple, does not cause corrosion in an apparatus and harm to the human bodies, and imparts high adhesiveness to a coating film. SOLUTION: This pretreatment method for the magnesium alloy member comprises contacting the magnesium alloy member with a metal powder, heating the metal powder and the magnesium alloy member contacted with the metal powder, and etching the surface of the magnesium alloy member by the solid state diffusion of magnesium in the magnesium member contacted with the metal powder into the metal powder. The metal powder is preferably either of aluminum, iron, nickel, or zinc, and particle diameters of the metal powder are preferably 300 μm or less. Furthermore, the heating temperature is preferably lower than the eutectic temperature of the magnesium alloy and the powder metal, in order to efficiently accelerate the solid diffusion, and sulfur hexafluoride gas is preferably used for the atmospheric gas in heating. COPYRIGHT: (C)2003,JPO