Metallic glass in bulk form is known to have superb strength and elastic response but very limited plastic deformation ability. Through machining the metaillinc glass into submicometer pillars, experiment found that metallic glass can actually sustain very large plastic doformation (see attached Figure). The detail of this finding can be found in our most recent publication: Z. W. Shan et al, Plastic flow and failure resistance of metallic glass: Insight from in situ compression of nanopillars, Phys. Rev. B 77, 155419 (2008) (6 pages).
I am now going to model a sample with metallic glass (Cu-Zr-Ti) under stress and temperature loads. I wonder whether there is some existing database to find material properties, in particular, the creep properties with respect to temperature and stresses. Then I can use these data as input for a FE analysis.
See an accompanying powerpoint presentation: The aged-rejuvenation-glue-liquid (ARGL) shear band model has been proposed for bulk metallic glasses (Acta Mater. 54 (2006) 4293), based on small-scale molecular dynamics simulations and thermomechanical analysis. The model predicts the existence of a critical lengthscale ~100 nm and timescale ~100 ps, above which melting occurs in shear-alienated glass. Large-scale molecular dynamics simulations with up to 5 million atoms have directly verified these predictions. When the applied stress exceeds the glue traction (computed separately before), we indeed observe maturation of the shear band embryo into bona fide shear crack, accompanied by melting.
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