Plasticity improvement of ZrCu-based bulk metallic glass by ex situ dispersed Ta particles

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2011-10, Vol.528 (28), p.8244-8248
• Main Authors: Li, J.B., Jang, J.S.C., Jian, S.R., Chen, K.W., Lin, J.F., Huang, J.C.
• Format: Article
• Language: English
• Subjects: Amorphous materials; Applied sciences; Casting; Composites; Compressive strength; Confinement; Dispersion hardening metals; Dispersion strengthening; Elasticity. Plasticity; Exact sciences and technology; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Mechanical properties at ambient temperature; Metallic glasses; Metals. Metallurgy; Particulate composites; Plasticity; Powder metallurgy. Composite materials; Production techniques; Tantalum; Volume fraction
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2011.08.006

[Display omitted] ► Shear bands are mainly arrested by the amorphous matrix–Ta interfaces in the ZrCu-based BMGCs. ► The ex situ Ta particles of BMGC distributed as a semi-uniform confinement zone. ► The confinement zone of Ta particles provide a plastic shielding of an opening crack tip to restrict shear band extension. ► The compression plasticity can be improved from 0% plastic strain (for the monolithic BMG) up to 22% plastic strain (BMGC with 10 vol.% Ta particles). The (Zr 48Cu 36Al 8Ag 8) 99.25Si 0.75-based bulk metallic glass composite (BMGC) rods ex situ dispersed with Ta particles (with a diameter of 2–4 mm) have been successfully fabricated by suction casting and characterized. These Ta-added BMGCs exhibit similar thermal properties in comparison with its base alloy counterpart, with relatively high glass forming ability (GFA). The results of compression test show that a superior mechanical performance with up to 22% compressive plastic strain, 1800 MPa yield strength and 1850 MPa fracture strength at room temperature can be obtained for the 2 mm diameter rod of the ZrCu-based BMGC with 10 vol.% Ta particles. These ex situ dispersed Ta particles (20 ± 8 μm) would arrange as semi-uniform confinement zones to restrict the shear band propagation. In addition, for a given Ta particle size, higher volume fraction particles would lead to more interfacial areas, shorter inter-particle spacings, smaller confinement zone sizes than the smaller volume fraction particles, and results in presenting larger compression plasticity.