Magnesium alloy member

Abstract

There is provided a magnesium alloy member that includes an aluminum-containing magnesium alloy material. The magnesium alloy material has a modified layer formed at a surface thereof in such a manner that at least a surface of the modified layer has a higher aluminum content than that of any unmodified base portion of the magnesium alloy material.

1 . A magnesium alloy member, consisting of or comprising: an aluminum-containing magnesium alloy material, the magnesium alloy material having a modified layer formed at a surface thereof in such a manner that at least a surface of the modified layer has a higher aluminum content than that of any unmodified base portion of the magnesium alloy material. 
     
     
         2 . The magnesium alloy member according to  claim 1 , wherein the aluminum content of the unmodified base portion is 2 mass % or higher. 
     
     
         3 . The magnesium alloy member according to  claim 1 , wherein the aluminum content of the surface of the modified layer is 1.5 times or more higher than that of the unmodified base portion. 
     
     
         4 . The magnesium alloy member according to  claim 1 , wherein the surface of the modified layer contains a magnesium-aluminum double hydroxide. 
     
     
         5 . The magnesium alloy member according to  claim 1 , further comprising:
 an adhesive resin material applied to at least part of the surface of the modified layer; and   a counterpart material bonded by the adhesive resin material to the surface of the modified layer.   
     
     
         6 . The magnesium alloy member according to  claim 5 , wherein the adhesive resin material is at least one selected from the group consisting of acrylic resins, urethane resins, epoxy resins and silicone resins. 
     
     
         7 . The magnesium alloy member according to  claim 1 , further comprising a coating material applied to the surface of the modified layer. 
     
     
         8 . The magnesium alloy member according to  claim 1 , wherein the modified layer is formed by surface treatment of the magnesium alloy material with an aqueous solution containing an inorganic chloride. 
     
     
         9 . The magnesium alloy member according to  claim 8 , wherein the inorganic chloride is a metal chloride. 
     
     
         10 . The magnesium alloy member according to  claim 8 , wherein the aqueous solution is an aqueous lubricant containing the inorganic chloride and a surfactant. 
     
     
         11 . The magnesium alloy member according to  claim 9 , wherein the metal chloride is at least one selected from the group consisting of lithium chloride, rubidium chloride, potassium chloride, barium chloride, strontium chloride, calcium chloride, sodium chloride and magnesium chloride. 
     
     
         12 . The magnesium alloy member according to  claim 10 , wherein the surfactant contains an alcohol. 
     
     
         13 . The magnesium alloy member according to  claim 12 , wherein the alcohol is at least one selected from the group consisting of monohydric, dihydric and trihydric alcohols each having a carbon number of 1 to 10.