METHOD FOR MANUFACTURING ALUMINUM ALLOY FUEL FILLER DOOR ASSEMBLY BY THIXOFORMING PROCESS USING A2024 ALUMINUM ALLOY

摘要

PURPOSE: To provide a method for manufacturing an aluminum alloy fuel filler door assembly for thixoforming process, the method for improving mechanical properties of a formed product and enabling the product to be formed in a complicated shape by manufacturing a fuel filler door assembly formed of an A2024 aluminum alloy by thixoforming process. CONSTITUTION: In a method for manufacturing a fuel filler door assembly formed of an A2024 aluminum alloy containing aluminum(Al) as a principal component, 0.50 wt.% of silicon(Si), 0.50 wt.% of iron(Fe), 3.8 to 4.9 wt.% of copper(Cu), 0.3 to 0.9 wt.% of manganese(Mn), 1.2 to 1.8 wt.% of magnesium(Mg), 0.10 wt.% of chromium(Cr), 0.28 wt.% of zinc(Zn), and 0.20 wt.% of zirconium(Zr) and titanium(Ti), the method is characterized in that the fuel filler door assembly is manufactured by thixoforming process using an A2024 aluminum alloy for thixoforming comprising 0.8 to 1.2 wt.% of silicon(Si) and 1.5 to 2.0 wt.% of copper(Cu), wherein the thixoforming process comprises a melting step of melting an aluminum alloy into molten aluminum alloy in a melting furnace; an electromagnetic stirring step of stirring the molten aluminum alloy by an electromagnetic field in an electromagnetic stirring device; a step of performing extrusion process on the molten aluminum alloy under the condition of an extrusion ratio of 20%; a reheating step of reheating a semi-molten billet obtained by the electromagnetic stirring; a forming step of pressing the heat treated semi-molten billet in a mold of an ejection molding equipment; a step of barrel treating the pickled and washed formed product using ceramic particles after pickling and washing the formed product; and a step of performing clear top coating on a resulting formed product after pickling and washing the barrel treated formed product again.