The present paper’s emphasis is on ductile BMGs. In spite of generation of a large body of scientific literature in the recent past on their fracture behaviour, consensus
about the micromechanisms that impart toughness to them is still elusive. High sensitivity of fracture toughness to composition and structural state of the alloy, and to the experimental variables such as temperature and strain rate are some possible reasons for this. An additional and important reason is the high degree of variability that is typical of the experimentally measured Kc values [9–11] which is the focus of this paper.Detailed experimental and computational studies by Tandaiya et al. [12] shed the following sequence of events taking place ahead of the notch tip when a fracture
specimen of a ductile BMG is loaded: (i) plastic deformation through extensive shear band formation and growth,which mitigates the stress concentration ahead of the tip,
(ii) initiation and stable growth of a crack inside the dominant shear band, (iii) onset of the dynamic crack growth or fast fracture, which results in the catastrophic fracture of the specimen. The stable crack growth occurs due to operation of Taylor’s fluid meniscus instability (FMI) mechanism inside the dominant shear band.
The present paper’s emphasis is on ductile BMGs. In spite of generation of a large body of scientific literature in the recent past on their fracture behaviour, consensus
about the micromechanisms that impart toughness to them is still elusive. High sensitivity of fracture toughness to composition and structural state of the alloy, and to the experimental variables such as temperature and strain rate are some possible reasons for this. An additional and important reason is the high degree of variability that is typical of the experimentally measured Kc values [9–11] which is the focus of this paper.Detailed experimental and computational studies by Tandaiya et al. [12] shed the following sequence of events taking place ahead of the notch tip when a fracture
specimen of a ductile BMG is loaded: (i) plastic deformation through extensive shear band formation and growth,which mitigates the stress concentration ahead of the tip,
(ii) initiation and stable growth of a crack inside the dominant shear band, (iii) onset of the dynamic crack growth or fast fracture, which results in the catastrophic fracture of the specimen. The stable crack growth occurs due to operation of Taylor’s fluid meniscus instability (FMI) mechanism inside the dominant shear band.
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