Scalable manufacturing of immiscible Al-Bi alloy by self-assembled nanoparticles

Immiscible Al-Bi alloy, with a miscibility gap in the liquid state is not only scientifically important, but also it can offer outstanding self-lubricating properties. However, it is still difficult to control the distribution and size of minority Bi phase during cooling and solidification. Here we show that by applying a scalable molten salt assisted incorporation process, TiC nanoparticles can be incorporated in Al matrix to produce Al-TiC master nanocomposites, which can be readily used to process Al-Bi immiscible alloy and restrict the size of minority Bi phase. TiC nanoparticles can be self-assembled on the Al-Bi interface and restrict Bi phase size substantially. In addition, submicron minority Bi phase can be achieved by combining the addition of nanoparticles with high cooling rates. Mechanical properties of Al-Bi immiscible alloys can be further enhanced by the addition of Cu element and cold rolling. (c) 2018 Elsevier Ltd. All rights reserved.