Ductile aluminum alloy, used for casting under pressure of structural and security components for motor vehicles, comprises alloying additions of silicon, element for reducing adherence on mold, and element for eutectic modification

A ductile aluminum alloy destined for casting under pressure comprises: (wt.%): (a) 2-6 silicon, less than 0.40 magnesium, less than 0.30 copper, less than 0.30 zinc, less than 0.50 iron and less than 0.30 titanium; (b) at least one element destined to reduce sticking on the mold, such as 0.3-2% manganese, 0.1-0.3 chromium, 0.1-0.3 cobalt, 0.1-0.3 vanadium or 0.1-0.4 molybdenum; (c) at least one element for eutectic modification, such as 50-500 ppm strontium, 20-100 ppm sodium or 30-120 ppm calcium; (d) other elements less than 0.05 each and less than 0.10 in total; and (e) remainder being aluminum. L'invention a pour objet un alliage d'aluminium ductile destiné à la coulée sous pression de composition (% en poids) :Si : 2-6 Mg < 0, 40 Cu < 0, 30 Zn < 0, 30 Fe < 0, 50 Ti < 0, 30, au moins un élément destiné à réduire le collage sur le moule tel que Mn (0, 3 - 2%), Cr (0, 1 - 0, 3), Co (0, 1 - 0, 3), V (0, 1 - 0, 3) et Mo (0, 1 - 0, 4),et au moins un élément modificateur de l'eutectique, tel que Sr (50 - 500 ppm), Na (20 - 100 ppm) et Ca (30 - 120 ppm),autres éléments < 0, 05 chacun et < 0, 10 au total, reste aluminium.