Flow Stress and Deformation Behavior of Zr-based Bulk Metallic Glass Composite in Supercooled Liquid Region

Zr계 비정질 복상 합금의 과냉 액상 영역에서의 유동 음력과 변형거동

  • 전현준 (포항공과대학교 신소재공학과) ;
  • 이광석 (포항공과대학교 항공재료센터) ;
  • 장영원 (포항공과대학교 신소재공학과)
  • Published : 2006.05.11

Abstract

The composition and structure of dendrite phase within $Zr_{76.11}Ti_{4.20}Cu_{4.51}Ni_{3.16}Be_{1.49}Nb_{10.53}$ bulk metallic glass (BMG) were confirmed by using an EPMA, XRD and TEM, respectively. The chief elements of dendrite phase were Zr-Ti-Nb and had a BCC structure. The thermal properties of this BMG have been then subsequently investigated by using a differential scanning calorimeter (DSC). The glass transition and crystallization onset temperatures were determined as $339.7^{\circ}C$ and $375.8^{\circ}C$ for this alloy, respectively. Mechanical properties have also been examined by conducting a series of uniaxial compression tests at various temperatures within supercooled liquid region under the strain rates between $10^{-4}/s$ and $3{\times}10^{-2}/s$. The deformation behavior of BMG composite within supercooled liquid region is similar to one of Vit-1 exhibiting amorphous single phase alloy. The flow stresses of BMG composite, however, are entirely higher than those of Vit-1 because dendrite phases are interfere with moving of atoms.

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