Purification of the Al2Cu intermetallic compound via zone melting crystallization technique

Abstract

The widespread interest in intermetallic compounds has driven the development of their structures and properties, as well as their applications as alternative structural and potentially functional materials. As more and more intermetallic compounds with complex compositions enter the application market, their performance improvement and sustainable recycling face many challenges, where the influence of impurities plays a crucial role. Here, we proposed the direct purification of intermetallic compounds by fractional crystallization and verified for the first time the feasibility and effectiveness of zone melting for the purification of intermetallic Al2Cu. After ten passes of zone melting, results showed no separation of Al and Cu, the major components of Al2Cu. Further analyses demonstrated the homogeneity and remelting stability of Al2Cu before and after zone melting. In addition, the total impurity concentrations at the front and the end of cast Al2Cu bars decreased with increasing number of passes, respectively. After ten passes of zone melting, Al2Cu bar with an initial purity of 3N exhibited higher refining efficiency than those with an initial purity of 4N. Among all impurities, the distribution coefficients of Fe, Si, Zn, and Ti were obviously less than unity (k < 1). Whereas the impurities Ca, Mg and Mn showed behaviors of distribution coefficients less than and/or close to unity.

Keywords

• Intermetallics
• Purification
• Al2Cu
• Zone melting
• Impurity