Magnesium alloy material

Abstract

A magnesium alloy material having high corrosion resistance is provided. The magnesium alloy material contains a magnesium alloy containing 7.3% to 16% by mass Al, wherein a region having an Al content of 0.8x % by mass or more and 1.2x % by mass or less occupies 50% by area or more, a region having an Al content of 1.4x % by mass or more occupies 17.5% by area or less, wherein x % by mass denotes the Al content of the entire magnesium alloy material, and there is substantially no region having an Al content of 4.2% by mass or less. The magnesium alloy material has small variations in Al concentration and includes a few regions having a very low Al content, thereby effectively preventing and retarding local corrosion. Thus, the magnesium alloy material has higher corrosion resistance than die-cast components having the same Al content.

1 . A magnesium alloy material, comprising a magnesium alloy that contains 7.3% by mass or more and 16% by mass or less Al and has a surface, wherein
 a region having an Al content of (x×0.8)% by mass or more and (x×1.2)% by mass or less occupies 50% by area or more in the surface,   a region having an Al content of (x×1.4)% by mass or more occupies 17.5% by area or less in the surface,   wherein x % by mass denotes the Al content of the entire magnesium alloy material, and
 there is substantially no region having an Al content of 4.2% by mass or less. 
   
     
     
         2 . The magnesium alloy material according to  claim 1 , wherein
 the region having an Al content of (x×0.8)% by mass or more and (x×1.2)% by mass or less occupies 70% by area or more in the surface, and   the region having an Al content of (x×1.4)% by mass or more occupies 5% by area or less in the surface.   
     
     
         3 . The magnesium alloy material according to  claim 1 , wherein a region having an Al content of (x×0.9)% by mass or more and (x×1.2)% by mass or less occupies 50% by area or more in the surface. 
     
     
         4 . The magnesium alloy material according to  claim 1 , wherein the total area of an intermetallic compound containing at least one of Al and Mg is 3% by area or less in a cross section in a surface side region of the magnesium alloy material. 
     
     
         5 . The magnesium alloy material according to  claim 1 , wherein the magnesium alloy material is a sheet. 
     
     
         6 . The magnesium alloy material according to  claim 1 , wherein the magnesium alloy material is a coiled long sheet. 
     
     
         7 . The magnesium alloy material according to  claim 1 , wherein the magnesium alloy material is a plastic worked component, which is a sheet that has been subjected to plastic working. 
     
     
         8 . A magnesium alloy component, comprising a magnesium alloy material according to  claim 1 . 
     
     
         9 . The magnesium alloy component according to  claim 8 , wherein the component is of an electronic device, electrical device, automobile, transportation equipment or aircraft. 
     
     
         10 . The magnesium alloy component according to  claim 8 , wherein the component is a housing for an electronic device, housing for electrical device, skeleton component or bag.