Quenching Sensitivity of an Aluminum Casting Alloy AlSi9Cu3

Abstract This publication investigates the influence of quenching velocity on the supersaturation of the solid solution state of the alloy AlSi9Cu3. The basic subject of these investigations are samples from a four-cylinder crankcase, cast in the laminar die-casting process. With regard to the examination methodology, two different implementations of solution annealing are used on specimens in the format of an M8 tensile specimen: Short-term solution annealing by means of diode lasers, which minimizes the influence on the casting structure and allows different cooling variations, as well as the conventional method of furnace solution annealing for very slow cooling rates of 0.1 °C/s. The samples are then cooled to room temperature after solution annealing and then subjected to artificial aging in the furnace (180 °C | 4 h). The subsequently determined R p0.2 yield strengths are correlated with the cooling rates, which allows the different precipitation behavior to be represented. Finally, the R p0.2 yield strength is set as a function of the cooling rate based on a mechanical material model.