Method of manufacturing heat treated sheet and plate with reduced levels of residual stress and improved flatness

Abstract

This invention describes a method of producing a flat aluminum sheet product by providing an aluminum alloy stock, hot working the aluminum alloy stock through preheating and hot rolling, side sawing the aluminum alloy stock, subjecting the aluminum alloy stock to solution heat treatment, cold rolling the aluminum alloy stock to reduce its thickness by about 0.25% to about 5%, and finally stretching the aluminum alloy stock.

1 . A method of producing an aluminum sheet or plate product comprising: 
 providing an aluminum alloy stock;    hot working said aluminum alloy stock;    side sawing said aluminum alloy stock;    solution heat treating and quenching said aluminum alloy stock;    cold rolling said aluminum alloy stock to reduce the thickness of said aluminum alloy stock by about 0.25% to about 5%; and    stretching said aluminum alloy stock.    
   
   
       2 . A method according to  claim 1  wherein: 
 providing an aluminum alloy stock selected from the 2XXX, 6XXX, or 7XXX series of aluminum alloys.    
   
   
       3 . A method according to  claim 1  wherein: 
 hot working comprises preheating and hot rolling.    
   
   
       4 . A method according to  claim 1  wherein: 
 solution heat treating said aluminum alloy stock from about 870° F. to about 1050° F.    
   
   
       5 . A method according to  claim 2  wherein: 
 solution heat truncating said 7XXX aluminum alloy stock from about 880° F. to about 900° F.    
   
   
       6 . A method according to  claim 2  wherein: 
 solution heat treating said 2XXX aluminum alloy stock from about 900° F. to about 930° F.    
   
   
       7 . A method according to  claim 2  wherein: 
 solution heat treating said 6XXX aluminum alloy stock from about 950° F. to about 1050° F.    
   
   
       8 . A method according to  claim 1  wherein: 
 stretching said aluminum alloy stock by about 0.5% to about 4%.    
   
   
       9 . A method according to  claim 1  wherein: 
 cold rolling and stretching said aluminum alloy stock by about 2% to about 6%.    
   
   
       10 . An aluminum sheet or plate exhibiting improved flatness and mechanical strength made by a process comprising: 
 providing an aluminum alloy stock;    hot working said aluminum alloy stock;    side sawing said aluminum alloy stock;    solution heat treating and quenching said aluminum alloy stock;    cold rolling said aluminum alloy stock to reduce the thickness of said aluminum alloy stock by about 0.25% to about 5%; and    stretching said aluminum alloy stock.    
   
   
       11 . An aluminum sheet or plate according to  claim 10  wherein: 
 providing an aluminum alloy stock selected from the 2XXX, 6XXX, or 7XXX series of aluminum alloys.    
   
   
       12 . An aluminum sheet or plate according to  claim 10  wherein: 
 hot working comprises preheating and hot rolling.    
   
   
       13 . An aluminum sheet or plate according to  claim 10  wherein: 
 solution heat treating said aluminum alloy stock from about 870° F. to about 1050° F.    
   
   
       14 . An aluminum sheet or plate according to  claim 11  wherein: 
 solution heat treating said 7XXX aluminum alloy stock from about 880° F. to about 900° F.    
   
   
       15 . An aluminum sheet or plate according to  claim 11  wherein: 
 solution heat treating said 2XXX aluminum alloy stock from about 900° F. to about 930° F.    
   
   
       16 . An aluminum sheet or plate according to  claim 11  wherein: 
 solution heat treating said 6XXX aluminum alloy stock from about 950° F. to about 1050° F.    
   
   
       17 . An aluminum sheet or plate according to  claim 10  wherein: 
 stretching said aluminum alloy stock by about 0.5% to about 4%.    
   
   
       18 . An aluminum sheet or plate according to  claim 10  wherein: 
 cold rolling and stretching said aluminum alloy stock by about 2% to about 6%.    
   
   
       19 . A method of producing an aluminum sheet or plate product comprising: 
 providing an aluminum alloy stock;    hot working said aluminum alloy stock;    side sawing said aluminum alloy stock;    solution beat treating and quenching said aluminum alloy stock;    cold rolling said aluminum alloy stock to reduce the thickness of said aluminum alloy stock by about 0.25% to about 5%; and    stretching said aluminum alloy stock by at about 0.5% to about 4%.    
   
   
       20 . A method according to  claim 19  wherein: 
 providing an aluminum alloy selected from the 2XXX, 6XXX, or 7XXX scrics of aluminum alloys.    
   
   
       21 . A method according to  claim 19  wherein: 
 hot working comprises preheating and hot rolling.    
   
   
       22 . A method according to  claim 19  wherein: 
 solution heat treating said aluminum alloy stock from about 870° F. to about 1050° F.    
   
   
       23 . A method according to  claim 20  wherein: 
 solution heat treating said 7XXX aluminum alloy stock from about 880° F. to about 900° F.    
   
   
       24 . A method according to  claim 20  wherein: 
 solution heat treating said 2XXX aluminum alloy stock from about 900° F. to about 930° F.    
   
   
       25 . A method according to  claim 20  wherein: 
 solution heat treating said 6XXX aluminum alloy stock from about 950° F. to about 1050° F.    
   
   
       26 . A method according to  claim 19  wherein: 
 cold rolling and stretching said aluminum alloy stock by about 2% to about 6%.