Influence of Copper and Iron on Solidification Characteristics of 356 and 380-Type Aluminum Alloys

Abstract

The influence of copper and iron on the solidification characteristics of two major aluminum foundry alloys was investigated. The thermal history during solidification of each sample was recorded and compared with the solidification path calculated from the multicomponent equilibrium and Gulliver-Scheil solidification models. SEM/EDX analysis and optical microscope were used to examine the microstructure of solidified samples. The amount of phases was also calculated from the latter model and compared with the observed microstructure. Binary interaction parameters were used in calculation for their practicality. Results show that the high content of copper and iron suppresses the liquiduses and final solidification temperatures. Moreover, the crystallization of Al2Cu and Al5FeSi is very sensitive to copper and iron content respectively; Al2Cu increases significantly when copper is added while Al5FeSi does greatly when iron content is higher.