An ordered metallic glass solid solution phase that grows from the melt like a crystal

作者：Chapman Karena W; Chupas Peter J; Long Gabrielle G^*; Bendersky Leonid A; Levine Lyle E; Mompiou Frederic; Stalick Judith K; Cahn John W

来源：Acta Materialia, 2014, 62: 58-68.

DOI：10.1016/j.actamat.2013.08.063

• Metallic glass
• Phase transformation
• Pair distribution function analysis
• X-ray scattering

We report structural studies of an Al-Fe-Si glassy solid that is a solid solution phase in the classical thermodynamic sense. We demonstrate that it is neither a frozen melt nor nanocrystalline. The glass has a well-defined solubility limit and rejects Al during formation from the melt. The pair distribution function of the glass reveals chemical ordering out to at least 12 angstrom that resembles the ordering within a stable crystalline intermetallic phase of neighboring composition. Under isothermal annealling at 305 degrees C the glass first rejects Al, then persists for approximately 1 h with no detectable change in structure, and finally is transformed by a first-order phase transition to a crystalline phase with a structure that is different from that within the glass. It is possible that this remarkable glass phase has a fully ordered atomic structure that nevertheless possesses no long-range translational symmetry and is isotropic. Published by Elsevier Ltd. on behalf of Acta Materialia Inc.

• 出版日期2014-1