Patent ID: 8152943

Claim:
A method for manufacturing a heat-treatable wrought metal plate product having a length, width and thickness direction, and having a gradient in engineering properties along at least one dimension of length or width direction of the plate product, comprising the steps of: a) providing a wrought metal plate product selected from a rolled, extruded or forged product, b) subjecting the plate product to a solution heat treatment, and c) rapidly cooling the plate product, d) ageing the cooled product comprising heat treating for time to arrive at different tempers across at least one dimension in a length or width direction of the plate product, said heat treating comprising heating the plate to raise temperature of the plate to temperature T 1 above ambient temperature, and applying to the heated plate a temperature gradient between temperature T 2 and T 3 , wherein T 2 >T 1 and T 2 >T 3 , wherein T 3 is at or above ambient temperature, across at least one length or width or thickness direction of the plate by applying a controlled heat-input into the plate from one side of the plate product to temperature T 2 and a controlled cooling to temperature T 3 from the plate product at the opposite side of the controlled heat input, wherein the heating the plate to raise temperature of the plate to temperature T 1 comprises heating a first wall of the plate to raise the temperature of the plate to temperature T 1 by directly applying heat to only the first wall, and wherein, while maintaining said first wall at about temperature T 1 , the controlled heat-input into the plate from one side of the plate product to temperature T 2 comprises heating a second wall of the plate to the temperature T 2 by directly applying heat to only the second wall, and the controlled cooling to temperature T 3 from the plate product at the opposite side of the controlled heat input comprises cooling a third wall of the plate opposed to the second wall by directly applying cooling to only the third wall to the temperature T 3 , the first wall extending between the second wall and the third wall, such temperature is controllable at the first, second and third walls of the plate, wherein a temperature gradient between T 2 and T 1 is in a range of 30° C. to 150° C., and wherein the product plate ages while applying the temperature gradient between T 2 and T 3 .