Formation of an abnormal lamellar precipitate in Cu–Cr–Zr–Mg–Ce nanocomposite during solution treatments

Abstract

An in situ nanoparticle reinforced Cu–0·4Cr–0·2Zr–0·15Mg–0·02Ce (wt-%) alloy was produced by vacuum centrifugal casting, followed by solid solution treating, water quenching. Microstructures of as-cast and solution-treated samples were studied by focus ion beam/scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy and X-ray diffraction measurements with special attention on an abnormal precipitation, composed of Mg₂Zr₅O₁₂, Cr single substance and CrCu₂(Zr, Mg), observed to form during solid solution treatment for the first time. Characterisation and formation mechanism of this lamellar precipitate was discussed as well as its microstructure evolution with solution treating temperature.

Keywords:

• Cu–Cr–Zr–Mg–Re alloy
• Solid solution
• Lamellar precipitate
• Mechanism
• Nanocomposite