CORRELATION BETWEEN SOLIDIFICATION PARAMETERS, MICROSTRUCTURE AND MECHANICAL PROPERTIES OF Zn-Al ALLOYS

ALICIA E. ARES; S.F. GUEIJMAN; RUBENS CARAM ; CARLOS SCHVEZOV

Puebla, México

Otro; INTERNATIONAL SCHOOL ON CRYSTAL GROWTH: FUNDAMENTALS, METHODS AND APPLICATIONS TO BIOLOGICAL AND -NANO-CRYSTALS? ISCG-2005; 2005

Universidad Nacional de México (UNaM)

The imposition of a wide range of operational conditions in foundry and casting process generates, as a direct consequence, a diversity of solidification structures. Structural parameters such as grain size and interdendritic spacings are highly influenced by thermal behavior of the metal/mould system during solidification, consequently imposing a close correlation between the described system and resulting microstructure. The mechanical properties of an alloy depend on solidification microstructural arrangement. Under this circunstance, the mechanical behavior of the alloy, represented by stresses and/or strains, will be defined by grain size, interdendritic spacings, casual porosities, segregated products and other phases. Expressions correlating the mechanical behavior with microstructure parameters are very useful for a previous planning of the solidification conditions in terms of a determined level of mechanical resistance which is intended to be attained, i.e. to settle a way of programming the microstructure and the mechanical properties as well. The aim of the present work is to investigate the influence of heat transfer on solidification microstructure of Zn-Al alloys and the correlation with mechanical properties. Experimental results include transient metal/mould and mold/environment heat transfer coefficients, secondary dendrite arm spacings, local solidifcation time and ultimate tensile strength as a function of solidification conditions imposed by the metal/mould system.