http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
박준영,Yoji Shibutani,Masato Wakeda 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.11
This study explores the influence of volume fraction of nanocrystals of Cu-Zr amorphous alloys on shear band formation. As the number of crystals with very tiny size increases, the strain localization, i.e. shear band, decreases without large drop of flow stress. The DPRs also depict no sudden drop and relatively high values. The strain state during the deformation represents a few shear bands at low volume fraction while there are no distinguishable shear bands at high volume fraction of nanocrystals.
Enhancement of Plasticity of Highly Density-Fluctuated Cu-Zr Amorphous Alloy
Park, Junyoung,Shibutani, Yoji,Wakeda, Masato The Japan Institute of Metals 2010 Materials transactions Vol.51 No.9
<P>This study explores the plastic deformability of highly density-fluctuated states due to the different thermal quenching process of the binary amorphous metals, Zr<SUB>67</SUB>Cu<SUB>33</SUB>, with embedded nanocrystals, Zr<SUB>2</SUB>Cu. To know the effect of local structural fluctuation, we prepare 5 computational models with Zr<SUB>2</SUB>Cu-nanocrystals that undergo rapid heat up and cool down. The region of nanocrystals is corresponding to the dense area because the intrinsic density of crystal is greater than that of amorphous structure. Due to the distribution of nanocrystals, the artificially constructed models have highly density-fluctuated structures (called “structural-inhomogeneity”). Strain localization during plastic deformation is much retarded at structural-inhomogeneous model in tensile loading. We found that structural-inhomogeneity promotes more homogenous deformation (call “deformable-homogeneity”, that is, retarded strain localization) even in globally recognized elastic region, while structural-homogeneity (almost close to pure amorphous structure) makes catastrophic inhomogeneous deformation (catastrophic shear band).</P>