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.