Phase formation and mechanical properties of Cu-Zr-Ti bulk metallic glass composites

• Published in: Metals and materials international Vol. 22; no. 6; pp. 1026 - 1032
• Main Authors: Kim, Byoung Jin, Yun, Young Su, Kim, Won Tae, Kim, Do Hyang
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01.11.2016; Springer Nature B.V; 대한금속·재료학회
• Subjects: Alloys; Amorphous materials; Characterization and Evaluation of Materials; Chemistry and Materials Science; Cooling rate; Copper; Crystal structure; Deformation; Engineering Thermodynamics; Eutectoid composition; Eutectoids; Heat and Mass Transfer; Intermetallic phases; Machines; Magnetic Materials; Magnetism; Manufacturing; Martensitic transformations; Materials Science; Mathematical models; Mechanical properties; Metallic glasses; Metallic Materials; Microscopy; Particulate composites; Phase transformations; Phase transitions; Plastic deformation; Processes; Solid Mechanics; Titanium; Volume fraction; Work hardening; Yield strength; Yield stress; 재료공학; compression test; bulk metallic glass composites; b2 phase; mechanical properties; crystal plasticity
• DOI: 10.1007/s12540-016-6386-x
• ISSN: 1598-9623

The effect of the type of the crystalline phase and its volume fraction on the mechanical property of Cu 50 Zr 50-x Ti x alloys (x = 0-10) bulk metallic glass composites has been investigated in this study. Up to 6 at% of Ti, B19’ phase particles distributed in the glassy matrix, while at 8 and 10% of Ti, B2 phase particles are retained in the glass matrix due to suppression of the eutectoid transformation of B2 phase and by avoidance of martensitic transformation of B2 into B19’. The volume fraction of crystalline phase is strongly dependent on the cooling rate. The larger volume fraction of the crystalline phases results in the lower yield stress, the higher plastic strain, and the more pronounced work hardening behavior. At the crystalline volume fraction below ~30%, the variation of the yield strength can be described by the rule of mixture model (ROM), while at the crystalline volume fraction higher than ~50% by the load-bearing model (LBM). At the crystal fractions between 30 and 50%, there is a yield strength drop and a transition from the ROM to the LBM. This transition is due to the formation of the crystalline structural framework at higher crystal fraction.