Patent ID: 6224693
Filing Date: 2001-05-01
Classification: B22D,C22F,Y10S

Abstract:
A method of quenching and artificially aging an aluminum alloy casting having a riser portion and a workpiece portion, said method comprising:selectively quench cooling the workpiece portion of the casting while maintaining the riser portion at a relatively higher temperature;initiating the quench when the casting is at elevated temperatures with its alloying elements in solid solution;proceeding with the quench to cool the workpiece portion sufficiently rapidly to inhibit precipitation of the alloy elements and thereby to maintain such elements in supersaturated solution within the aluminum matrix,discontinuing the quench when the workpiece portion is cooled to a temperature which is at or below the range for artificial aging;artificially aging said workpiece portion within a range of temperatures and over an effective time period appropriate for such aging of the aluminum alloy casting workpiece primarily by means of residual heat flowing from the riser portion.