摘要： SEM micrographs of the tilt- and suction-cast samples where near the notch root after bending test; (a) Zr53Cu30Ni9Al8 and (b) (Zr53Cu30Ni9Al8)99.25Si0.75 are tilt-cast samples, (c) Zr53Cu30Ni9Al8 and (d) (Zr53Cu30Ni9Al8)99.25Si0.75 are suction-cast samples. Note that the tilt-cast Zr-53 BMG without Si possesses the best fracture toughness among these BMGs in this study. [Display omitted] •The highest fracture toughness of 120MPam was achieved for the tilt-cast Zr53Cu30Ni9Al8.•Shear bands in the tilt-cast Zr53Cu30Ni9Al8 plate (Fig. 7(a)) appear in a finer and denser manner.•Tilt casting could effectively reduce the micro-porosity in the cast BMGs.•Si minor addition would degrade appreciably the fracture toughness. In order to clarify the effects of tilt- or suction-cast processing and microalloying of minor Si on the three-point bending fracture toughness of the Zr-based bulk metallic glasses (BMGs), the tilt-cast and suction-cast Zr53-based and Zr48-based BMGs with and without Si were studied. The results revealed that the tilt-cast specimens present much better fracture toughness than the suction-cast counterparts as a result of their lower degrees of residual porosity. In addition, the microalloying of Si to 0.75at.% in these BMGs would impose negative effects on their fracture toughness. The highest fracture toughness of 120MPam was achieved for the tilt-cast Zr53Cu30Ni9Al8. Moreover, the morphology of fracture surface, the calculated fracture energy, and the Poisson’s ratio show the similar trend to prove that the tilt-cast Zr-53 BMG without Si possesses the best fracture toughness among these BMGs in this study. 出版者： Kidlington: Elsevier B.V 出版日期： 2014-11-25 出處： Journal of alloys and compounds, 2014-11, Vol.614, p.87-93 版權： 2014 Elsevier B.V. 版權： 2015 INIST-CNRS 識別號： ISSN: 0925-8388 識別號： EISSN: 1873-4669 識別號： DOI: 10.1016/j.jallcom.2014.06.062
