This specification covers aluminum-alloy investment castings. Unless otherwise specified, only aluminum alloy conforming to the requirements shall be used in the remelting furnace from which molten metal is taken for pouring directly into castings. The castings shall conform to the chemical composition requirements specified. The determination of chemical composition shall be made in accordance with suitable chemical (Test Methods E 34), or spectrochemical (Test Methods E 607 and E 1251) methods. Unless otherwise specified, only aluminum alloy conforming to the requirements shall be used in the remelting furnace from which molten metal is taken for pouring directly into castings. Foundry control shall consist of examination of castings by radiographic or other approved methods for determining internal discontinuities until the gating, pouring, and other foundry practices have been established to produce castings meeting the required quality standards. The tensile properties shall be determined in accordance with Test Methods B 557 and B 557M. Heat treatment of castings shall be performed in accordance with Practice B 917/B 917M.

1.1 This specification covers aluminum-alloy investment castings designated as shown in Table 1.

1.2 This specification is not intended for aluminum-alloy investment castings used in aerospace applications.

1.3 Alloy and temper designations are in accordance with ANSI H35.1/H35.1 (M). The equivalent Unified Numbering System alloy designations are in accordance with Practice E527.

1.4 Unless the order specifies the “M” specification designation, the material shall be furnished to the inch-pound units.