title: Two-phase quasi-equilibrium in β-type Ti-based bulk metallic glass composites.
abstract: The microstructural evolution of cast Ti/Zr-based bulk metallic glass composites (BMGCs) containing β-Ti still remains ambiguous. This is why to date the strategies and alloys suitable for producing such BMGCs with precisely controllable volume fractions and crystallite sizes are still rather limited. In this work, a Ti-based BMGC containing β-Ti was developed in the Ti-Zr-Cu-Co-Be system. The glassy matrix of this BMGC possesses an exceptional glass-forming ability and as a consequence, the volume fractions as well as the composition of the β-Ti dendrites remain constant over a wide range of cooling rates. This finding can be explained in terms of a two-phase quasi-equilibrium between the supercooled liquid and β-Ti, which the system attains on cooling. The two-phase quasi-equilibrium allows predicting the crystalline and glassy volume fractions by means of the lever rule and we succeeded in reproducing these values by slight variations in the alloy composition at a fixed cooling rate. The two-phase quasi-equilibrium could be of critical importance for understanding and designing the microstructures of BMGCs containing the β-phase. Its implications on the nucleation and growth of the crystalline phase are elaborated.
authors.affiliation: Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, China.|IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, D-01069 Dresden, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Zhang
authors.affiliation: IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, D-01069 Dresden, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Pauly
authors.affiliation: Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, China.
authors.forename: M Q
authors.initials: MQ
authors.lastname: Tang
authors.affiliation: IFW Dresden, Institute for Complex Materials, P.O. Box 27 01 16, D-01069 Dresden, Germany.|TU Dresden, Institute of Materials Science, D-01062 Dresden, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Eckert
authors.affiliation: Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, China.
authors.forename: H F
authors.initials: HF
authors.lastname: Zhang