Scattering mechanical performances of brittle La- and Mg-based BMGs are found in the present study. Upon dynamic loading, there exist largely scattered fracture strengths even if the strain rates are under the same order, and the BMG systems are the same. The negative strain rate dependence for La- and Mg-based BMGs is obtained, i.e., a decreased fracture strength is dominating from quasi-static to dynamic compression. At cryogenic temperatures, distinguishingly low fracture strengths are available for these two brittle BMGs, and decreased tolerance to accommodate strains makes BMGs more and more brittle. It is concluded that the scattering mechanical performances of brittle BMGs should be carefully evaluated before actual applications. AIP Advances, 2014 High-energy synchrotron X-ray diffraction for (a) La-based and (b) Mg-based BMGs. The fractographes of Mg-based BMGs after dynamic loading at room temperature. Power-like particles after high-speed dynamic compression shown in (a); high-magnification of particles displayed in (b); ruffles with found on the fracture surfaces shown in (c); and periodic stripes on the smooth part shown in (d). |
