High strength extrusion alloy

Abstract

This disclosure provides an aging process or a method for aging aluminum alloys. For example, the aging process can be performed on 6xxx Al—Si—Mg—Cu aluminum alloys to result in production of such alloys with improved intergranular corrosion (IGC) resistance. The disclosed aging process includes subjecting a solution heat treated and quenched 6xxx aluminum alloy to a temperature above an aging hardening temperature of said alloy but below the solution heat treatment temperature for a short period of time, and then subjecting said alloy to an aging heat treatment at an aging hardening temperature.

1 . A method comprising:
 subjecting an alloy to a first temperature for a first time duration,
 wherein the first temperature is greater than an aging hardening temperature of the alloy and below a solution heat treatment temperature; and 
   subjecting the alloy to a second temperature for a second time duration.   
     
     
         2 . The method of  claim 1 , further comprising:
 subjecting the alloy to a solution heat treatment at the solution heat treatment temperature, prior to the subjecting the alloy to the first temperature.   
     
     
         3 . The method of  claim 1 , wherein the second temperature is an aging hardening temperature. 
     
     
         4 . The method of  claim 1 , wherein the alloy includes a solution heat treated and quenched alloy. 
     
     
         5 . The method of  claim 1 , wherein the alloy includes a 6xxx aluminum alloy. 
     
     
         6 . The method of  claim 1 , wherein the alloy includes a 6xxx Al—Si—Mg—Cu aluminum alloy. 
     
     
         7 . The method according to  claim 1 , further comprising:
 obtaining a resulting alloy,
 wherein the resulting alloy has an improved intergranular corrosion (IGC) resistance. 
   
     
     
         8 . The method according to  claim 1 , wherein the first temperature is from 200° C. to 210° C. 
     
     
         9 . The method according to  claim 1 , wherein the first time duration is from 5 minutes to 20 minutes. 
     
     
         10 . The method according to  claim 1 , wherein the second temperature is from 150° C. to 200° C. 
     
     
         11 . The method according to  claim 1 , wherein the second time duration is from 30 minutes to 3 hours. 
     
     
         12 . A method comprising:
 subjecting an aluminum alloy to a first temperature for a first time duration; and   subjecting the aluminum alloy to a second temperature for a second time duration,   wherein the first temperature is higher than the second temperature,   wherein the first time duration is from 5 minutes to 20 minutes.   
     
     
         13 . The method according to  claim 12 , wherein the first temperature is from 200° C. to 210° C. 
     
     
         14 . The method according to  claim 12 , wherein the second temperature is from 150° C. to 200° C. 
     
     
         15 . The method according to  claim 12 , wherein the second time duration is from 30 minutes to 3 hours. 
     
     
         16 . The method according to  claim 2 , further comprising:
 obtaining a resulting alloy,
 wherein the resulting alloy has an improved intergranular corrosion (IGC) resistance. 
   
     
     
         17 . The method according to  claim 3 , further comprising:
 obtaining a resulting alloy,
 wherein the resulting alloy has an improved intergranular corrosion (IGC) resistance. 
   
     
     
         18 . The method according to  claim 4 , further comprising:
 obtaining a resulting alloy,
 wherein the resulting alloy has an improved intergranular corrosion (IGC) resistance. 
   
     
     
         19 . The method according to  claim 5 , further comprising:
 obtaining a resulting alloy,
 wherein the resulting alloy has an improved intergranular corrosion (IGC) resistance. 
   
     
     
         20 . The method according to  claim 6 , further comprising:
 obtaining a resulting alloy,
 wherein the resulting alloy has an improved intergranular corrosion (IGC) resistance.