Non-heat treated magnesium alloy sheet with excellent formability at room temperature in which segreation is minimized

Abstract

Disclosed herein is a non-heat treatable magnesium alloy sheet, including: 1˜3 wt % of aluminum (Al); 0.5˜3 wt % of tin (Sn); and a balance of magnesium, wherein the maximum deviation of average Vickers hardness (Hv) thereof, caused by center segregation and inverse segregation, is 10 Hv or less.

1 . A non-heat treatable magnesium alloy sheet, comprising:
 1˜3 wt % of aluminum (Al); 0.5˜3 wt % of tin (Sn); and a balance of magnesium, wherein a maximum deviation of average Vickers hardness (Hv) thereof, caused by center segregation and inverse segregation, is 10 Hv or less.   
     
     
         2 . The non-heat treatable magnesium alloy sheet of  claim 1 , wherein the magnesium alloy sheet is formed by twin-roll strip casting, and has a microstructure of a Mg 2 Sn secondary phase. 
     
     
         3 . The non-heat treatable magnesium alloy sheet of  claim 2 , wherein the Mg 2 Sn secondary phase has a volume fraction of 5% or less. 
     
     
         4 . The non-heat treatable magnesium alloy sheet of  claim 1 , wherein the magnesium alloy sheet has a yield strength of 200 MPa or more and a limit dome height (LDH) of 5 mm or more. 
     
     
         5 . The non-heat treatable magnesium alloy sheet of  claim 1 , wherein the magnesium alloy sheet has a yield strength of 200 MPa or more and a limit dome height (LDH) of 6 mm or more. 
     
     
         6 . The non-heat treatable magnesium alloy sheet of  claim 1 , wherein a volume fraction of tension twins inclined at an angle of 85˜90° to parent grains is 5% or more. 
     
     
         7 . The non-heat treatable magnesium alloy sheet of  claim 2 , wherein the magnesium alloy sheet has a yield strength of 200 MPa or more and a limit dome height (LDH) of 5 mm or more. 
     
     
         8 . The non-heat treatable magnesium alloy sheet of  claim 3 , wherein the magnesium alloy sheet has a yield strength of 200 MPa or more and a limit dome height (LDH) of 5 mm or more. 
     
     
         9 . The non-heat treatable magnesium alloy sheet of  claim 2 , wherein the magnesium alloy sheet has a yield strength of 200 MPa or more and a limit dome height (LDH) of 6 mm or more. 
     
     
         10 . The non-heat treatable magnesium alloy sheet of  claim 3 , wherein the magnesium alloy sheet has a yield strength of 200 MPa or more and a limit dome height (LDH) of 6 mm or more. 
     
     
         11 . The non-heat treatable magnesium alloy sheet of  claim 2 , wherein a volume fraction of tension twins inclined at an angle of 85˜90° to parent grains is 5% or more. 
     
     
         12 . The non-heat treatable magnesium alloy sheet of  claim 3 , wherein a volume fraction of tension twins inclined at an angle of 85˜90° to parent grains is 5% or more.