Abstract: This invention relates to master alloy hardeners for use in preparing aluminum base alloys. The respective concentrations of the alloying elements in the master alloy hardener are a multiple equal to or greater than 2 of the concentrations of such elements in the base alloy, and the ratios of the alloying elements in the master alloy hardener to each other are the same as the ratios of the alloying elements in the base alloy. After the aluminum base alloy and the concentration of each alloying element therein are identified, a desired multiple of such concentrations is determined. An aluminum master alloy is prepared that contains the alloying elements at concentrations equivalent to such multiple of the corresponding concentrations of the elements in the base alloy. The master alloy hardeners are added to commercially pure aluminum to provide the desired base alloy.

Abstract: A process for hardening aluminum comprises the steps of adding a magnesium hardener to molten aluminum wherein the hardener has a magnesium content in the range of 64-72 wt % based on the weight of the hardener, with a remaining portion of the hardener comprising aluminum. The process may further include the steps of preheating the hardener prior to adding the hardener to the aluminum for decreasing a temperature differential between the hardener and the aluminum so as to stabilize the hardener and prevent shattering thereof.

Abstract: A process for producing a magnesium alloy aluminum hardener comprises the steps of providing magnesium alloy scrap, wherein the scrap comprises aluminum present in a range of 1-10 wt. % based on the weight of the scrap and at least one of zinc present in a range of 0.1-3 wt. % based on the weight of the scrap and manganese present in a range of 0.1-3 wt. % based on the weight of the scrap, wherein a remaining portion of the scrap comprises magnesium; providing molten aluminum; and adding the scrap to the molten aluminum until the hardener is produced having a magnesium content in a range of 64-72 wt. % based on the weight of the hardener, with a remaining portion of the hardener comprising aluminum and at least one of zinc and manganese.

Abstract: This invention relates to master alloy hardeners for use in preparing aluminum base alloys. The respective concentrations of the alloying elements in the master alloy hardener are a multiple equal to or greater than 2 of the concentrations of such elements in the base alloy, and the ratios of the alloying elements in the master alloy hardener to each other are the same as the ratios of the alloying elements in the base alloy. After the aluminum base alloy and the concentration of each alloying element therein are identified, a desired multiple of such concentrations is determined. An aluminum master alloy is prepared that contains the alloying elements at concentrations equivalent to such multiple of the corresponding concentrations of the elements in the base alloy. The master alloy hardeners are added to commercially pure aluminum to provide the desired base alloy.

Abstract: Improved aluminum master alloys containing strontium and boron are provided for simultaneously modifying and grain refining Al alloys, and in particular, hypoeutectic Al-Si alloys. The improved master alloy contains, by weight percent, about 0.20-20% Sr, 0.10-10% B, and the balance Al with impurities. The master alloy may also contain about 0.20 to about 20% Si by weight percent. The master alloys have a high degree of ductility for purposes of forming continuously rolled master alloy rod stock.