CORRELATION OF THERMAL, TENSILE AND CORROSION PARAMETERS OF ZN-AL ALLOYS WITH COLUMNAR, EQUIAXED AND TRANSITION STRUCTURES

ALICIA ESTHER ARES; LILIANA MABEL GASSA; SERGIO F. GUEIJMAN ; CARLOS E. SCHVEZOV

San Francisco, California, USA

Simposio; Shape Casting: Third International Symposium; 2009

The Metallurgical Society of AIME

The columnar to equiaxed transition (CET) has been examined in different wrought and castingalloys for many years and the metallurgical significance of CET has been treated in severalarticles. Experimental observations in the literature have focused on thermal parameters likecooling rate, velocity of the liquidus and solidus fronts, local solidification time, temperaturegradients and recalescence. The objective of the present research consist on studying theinfluence of solidification thermal parameters on the type of structure (columnar, equiaxial orwith the CET) and on the secondary dendritic spacing in Zn-Al alloys (Zn-1%Al and Zn-4wt%Al, weight percent). Also, correlate the thermal and structural parameters of these alloyswith tensile and corrosion behavior. The results show that Zn-4wt%Al alloys are more resistantto the corrosion that Zn-1wt%Al, independently of the structure. Also, in both alloys theequiaxed structures presented a better tensile resistance than the columnar and CET zones.