Análisis de la solidificación de aleaciones ZN-AL a partir del método de Newton

The undercoolings of the primary and eutectic phases were determined in three Zn-Al alloys by the experimental cooling curves associated. The compositions of the alloys considered in this study were Zn-3%wAl, Zn-6%w Al and Zn-11% w Al in order to determinate the influence of the primary phase in the morphology obtained by the euetecic microsconstituent at the end of the solidification and its relationship with the underccoling registered in each step. The experimental cooling curves were obtained by a thermocouple type K inserted laterally at the center of a metallic mould of stainless steel 304, which dimentions were 4 cm of diameter and 7.5 cm of lengh. This thermocouple was connected to a data adqusiitior system and a computer in order to register these data in an electronic file. These data were processed following the algorithm of NTA method. The results obtained showed that a minor undercoolig is associated with a lamellar eutectic morphology.