![\"Impurity](\"https:\/\/aluminiumceramicfiber.com\/wp-content\/uploads\/2020\/11\/Impurity-Elements-of-3000-Series-Alloy.jpg\")
<\/p>\nThe impurity elements of 3000 series alloy generally include Fe, Si, Mg, Zn. Fe can be dissolved in MnAl6 to form (FeMn)Al6 compound, thereby reducing the solubility of Mn in Al. 0.4%\uff5e0.7% Fe is added to the alloy, but Fe+Mn must not exceed 1.85%, which can effectively refine the grains of the sheet after annealing. Otherwise, a large amount of coarse flake (FeMn) Al6 compound will be formed, which will be significant to reduce the mechanical properties and process performance of the alloy.<\/p>\n
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Impurity Elements of 3000 Series Alloy<\/strong><\/p>\n Si is a harmful impurity. Si and Mn form a complex ternary phase T (Al12Fe3Si2) or \u03b2 (Al9Fe2Si2) phase, which affects the beneficial effects of Fe. Therefore, the Si in the alloy should be controlled below 0.6%. Si will also reduce the solubility of Mn in Al and has a greater influence than Fe. A small amount of Mg (approximately 0.3%) can significantly refine the annealed grains of the alloy and help improve its tensile strength, but it is not good for the surface gloss of the annealed material.<\/p>\n However, in Al-Mg-Mn series alloys, Mg is used as an alloying element. Adding 0.3% 1.3% Mg can increase the strength of the alloy and decrease the elongation (annealed state). 0.05%0.5%Cu in the alloy can significantly increase its tensile strength, but a small amount of copper (0.1%) can reduce the corrosion resistance of the alloy, so the Cu content in the alloy should be controlled below 0.2%. When the Zn content is less than 0.5%, it has no obvious effect on the mechanical properties and corrosion resistance of the alloy. Considering the welding performance of the alloy, the Zn content is limited to less than 0.2%.<\/p>\n