Aluminum forming method

Abstract

A method for forming a component to a target shape from an aluminium blank workpiece is disclosed, the method comprising: (a) cold forming an aluminium blank workpiece between a set of dies, thereby producing a component fully or partially formed to a target shape; (b) solution heat treating the fully or partially formed component by heating to or above a solution heat treatment (SHT) temperature and substantially maintaining that temperature until SHT has been completed, thereby producing a solution heat treated fully or partially formed component; and (c) quenching the solution heat treated fully or partially formed component whilst held between a set of dies, wherein holding between the dies may provide additional forming at the same time as quenching, to produce a component fully formed to the target shape.

1 . A method for forming a component to a target shape from an aluminium blank workpiece, the method comprising the steps of:
 (a) cold forming an aluminium blank workpiece between a set of dies, thereby producing a component fully or partially formed to a target shape;   (b) solution heat treating the fully or partially formed component by heating to or above a solution heat treatment (SHT) temperature and substantially maintaining that temperature until SHT has been completed, thereby producing a solution heat treated fully or partially formed component; and   (c) quenching the solution heat treated fully or partially formed component whilst held between a set of dies, wherein holding between the dies may provide additional forming at the same time as quenching, to produce a component fully formed to the target shape.   
     
     
         2 . The method according to  claim 1 , wherein:
 in step (a) the aluminium workpiece is cold formed at a temperature between 0 and 100 degrees centigrade, preferably from 15 to 30 degrees centigrade.   
     
     
         3 . The method according to  claim 1 , wherein:
 the temperature of the cold forming step (a) is controlled by the set of dies, and/or temperature treatment of the aluminium blank workpiece in a step prior to cold forming in step (a).   
     
     
         4 . The method according to  claim 1 , wherein:
 the component formed in step (a) is partially formed to the target formed component shape and the partially formed component is fully formed to the target formed component shape during quenching in step (c).   
     
     
         5 . The method according to  claim 1 , wherein:
 the component formed in step (a) is formed to from 20% to 100% of the target formed component shape.   
     
     
         6 . The method according to  claim 1 , wherein:
 the set of dies are provided with a grip with one or more protrusions configured to grip the workpiece during forming and thereby control the flow of the workpiece during forming, and wherein one of step (a) and step (c) of the method further comprise using the grip to grip the workpiece during forming.   
     
     
         7 . The method according to  claim 1 , wherein:
 the set of dies used in step (a) is a first set of dies and the set of dies used in step (c) is a second set of dies, or wherein the set of dies used in step (a) and the set of dies used in step (c) are the same set of dies.   
     
     
         8 . (canceled) 
     
     
         9 . (canceled) 
     
     
         10 . The method according to  claim 1 , wherein:
 the aluminium blank workpiece is at least one of fully or partially annealed or is in a T4 or a T6 temper condition state.   
     
     
         11 . The method according to  claim 1 , wherein:
 the aluminium blank workpiece used is an aluminium alloy.   
     
     
         12 . The method according to  claim 1 , wherein:
 the aluminium blank workpiece used is a heat-treatable aluminium alloy or a non-heat-treatable aluminium alloy.   
     
     
         13 . The method according to  claim 1 , wherein:
 the aluminium blank workpiece is one of an AA2XXX, AA6XXX, or AA7XXX series alloy.   
     
     
         14 . The method according to  claim 1 , wherein:
 the aluminium alloy is an AA5XXX series alloy.   
     
     
         15 . The method according to  claim 1 , wherein:
 the aluminium blank workpiece used is annealed aluminium alloy sheet and is an AA6082 aluminium alloy in an O condition state.   
     
     
         16 . The method according to  claim 15 , wherein:
 the solution heat treating step (b) further comprises heating the component formed in step (a) to a temperature within the range from 450 to 600 degrees centigrade.   
     
     
         17 . The method according to  claim 1 , wherein:
 after step (b) the solution heat treated fully or partially formed component is rapidly transferred to the set of dies in step (c) within from 1 to 20 seconds.   
     
     
         18 . The method according to  claim 1 , wherein:
 in step (c) the set of dies are maintained at a temperature of between 0 to 250 degrees centigrade.   
     
     
         19 . The method according to  claim 13 , wherein:
 in step (c) the quenching is carried out to a temperature of below an artificial ageing temperature of the material if the material is a heat-treatable aluminium alloy or to a temperature below a metallurgically stable temperature of the material if the material is a non-heat-treatable aluminium alloy.   
     
     
         20 . The method according to  claim 1 , wherein:
 in step (c) the quenching is carried out at a rate of from 15 degrees centigrade per second and above to 200 degrees centigrade per second and above.   
     
     
         21 . The method according to  claim 1 , wherein:
 the method further comprises a step of artificially aging the formed component to obtain improved mechanical properties.   
     
     
         22 . The method according to  claim 1 , further comprising:
 using a lubricant to lubricate the interface between the set of dies and the workpiece in step (a) and the set of dies and the fully or partially formed component in step (c).   
     
     
         23 . (canceled)