Patent ID: 9039850
Filing Date: 2015-05-26
Classification: B21J,B21K,C22C,C22F

Abstract:
1. A method of manufacturing an aluminum alloy forging material, comprising: obtaining an aluminum alloy ingot having a structure in which a secondary dentrite arm spacing (DAS) is 40 μm or less and an average grain diameter of crystallized substances is 8 μm or less by continuously casting a molten aluminum alloy having an aluminum composition consisting of: Si: 0.80 to 1.15 mass %; Fe: 0.2 to 0.5 mass %; Cu: 3.8 to 5 mass %; Mn: 0.8 to 1.15 mass %; Mg: 0.5 to 0.8 mass %; Zr: 0.05 to 0.13 mass %; and Ti contained in such an amount that a sum of Ti and Zr is 0.2 mass % or less, and the balance being Al and inevitable impurities, wherein the alloy composition satisfies a Cu/Mg ratio of 8 or less, Ti is added in a form of a 5Ti-1B mother alloy, and Ti/Zr ratio satisfies 0.3 or higher; obtaining an aluminum alloy cast product by subjecting the aluminum alloy ingot to homogenization treatment for holding the product for one hour or more at temperatures of 450 to 510° C., hot forging the aluminum alloy cast product under temperature conditions of 400 to 510° C., subjecting the aluminum alloy cast product to a solution treatment under temperature conditions of 450 to 510° C., and subjecting the aluminum alloy cast product to an aging treatment, wherein the aluminum alloy cast product is constituted as the aluminum alloy forging material.