High strength Al–Zn–Mg–Cu–Ni–Si alloy with improved casting properties

Abstract

The casting properties of high strength Al-7Zn-7Mg-1Cu-3Ni-3Si(wt-%) alloy are described. Compared with common Al-Zn-Mg-Cu alloys, an improvement of casting properties has been achieved by adding elements (Ni, Mg, Si) that form eutectic phases, thus reducing the solidification interval of the alloy. A comparison of thermal cooling curves, castability and hot tearing tendency has been carried out for three alloys: Al-7Zn-2Mg-1Cu (structure consists mainly of solid solution), quasi-ternary eutectic alloy Al-7Zn-7Mg-1Cu-3Ni-3Si and the common casting alloy Al-10Si. In addition, the effect of melt protection against oxidation on castability has been evaluated. It is shown that the casting properties of the protected quasi-ternary eutectic alloy are significantly better than those of the common Al-7Zn-2Mg-1Cu alloy and that they achieve a level close to that of Al-10Si alloy.

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References

MONDOLFO

L. F.

: ‘Struktura i svojstva aljuminijevych splavov’, 1979, Moscow, Metallurgija Moskva (in Russian).

KOLOBNEV

I. F.

: ‘Terrnféeskaja obrabotka aljuminijevych spla-vov’, 1961, Moscow, Metallurgizdat, (in Russian).

TAGIEV

and HOLE

: Aluminium, 1996, 4, 246.

BELOV

N. A.

and TAGIEV

: CVetnaja Metaa, 1991, 2, 95 (in Russian).

KUBiftK

and E. TAGUEV et al.: Kovove Mater, 1993,4, 329 (in Czech).

VOITÉCH

and E. TAGIIEV et al.: Proc. 18th Natl. Conf. on ‘Heat treatment with international participation’, Brno, Czech Republic, November 2000, Association for Heat Treatment of Metals, 365 (in Czech).

TAGIEV

, HOLEftK

and BELOV

: Proc. Conf. on ‘Aluminium alloys’, Grenoble, France, July 1996, SF2M, Part 1, 289.