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The effects of Ta addition on the microstructure and mechanical properties of Ti40Zr25Ni8Cu9Be18 bulk amorphous alloy were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM), scan electron microscopy (SEM) and compressive testing. As a result, the addition of Ta (0-8at%) prompted the successive precipitation of quasicrystalline phase, CuTi2 phase and bcc β-Ti solid solution. Additionally, the addition of less Ta content (3at%-5at%) led to the formation of amorphous ma- trix/nanoquasicrystal/CuTi2 complex phase structure; and nanoquasicrystals, as reinforcement precipitates, improved the fracture strength of Ti-Zr-Ni-Cu-Be-Ta alloys, which led to the high compressive fracture strength 1856 MPa of Ta5 alloy. With increasing Ta content (5at%-8at%), although the ductile dendritic β-Ti solid solution was precipitated, the strength and plasticity decreased to a great extent resulting from the growth of quasicrystalline phase and CuTi2 phase.
The effects of Ta addition on the microstructure and mechanical properties of Ti40Zr25Ni8Cu9Be18 bulk amorphous alloys were investigated by using X-ray diffraction (XRD), transmission electron microscopy (TEM), scan electron microscopy (SEM) and compressive testing. As a result, the addition of Ta (0-8 at%) suggests the successive precipitation of quasic crystalline phase, CuTi2 phase and bcc β-Ti solid solution. trix / nanoquasicrystal / CuTi2 complex phase structure; and nanoquasicrystals, as reinforcement precipitates, improved the fracture strength of Ti-Zr-Ni-Cu-Be-Ta alloys, which led to the high compressive fracture strength 1856 MPa of Ta5 alloy. With increasing Ta content (5 at% -8 at%), although the ductile dendritic β-Ti solid solution was precipitated, the strength and plasticity decreased to a great extent resulting from the growth of quasic crystalline phase and CuTi2 phase.