Impact Fracture Behaviors of Zr-Based Bulk Amorphous Metals

Zr-기 벌크 아몰퍼스 금속의 충격 파괴 거동

  • 고동균 (안동대학교 대학원 기계공학과) ;
  • 정영진 (안동대학교 대학원 기계공학과) ;
  • 신형섭 (안동대학교 기계공학부) ;
  • 오상엽 (가톨릭상지대학)
  • Published : 2003.11.05

Abstract

The fracture behaviors of Zr-based bulk amorphous metals(BAMs) having compositions of $Zr_{55}Al_{10}Ni_{5}Cu_{30}$, were investigated under impact loading and quasi-static conditions. For experiments, a newly devised instrumented impact testing apparatus and the subsize Charpy specimens were used. The influences of loading rate and the notch shape on the fracture behavior of the Zr-based BAM were examined. The Zr-based BAMs showed an elastic deformation behavior without any plastic deformation on it before fracture. Most fracture energies were absorbed in the process of the crack initiation. The maximum load and fracture absorbed energy under quasi-static condition were larger than those under impact condition. However, there existed relatively insignificant notch shape effect. Fracture surfaces under impact loading were smoother than those under quasi-static loading. The absorbed fracture energy appeared differently depending on the extent of the vein-like pattern region due to the shear bands developed at the notch tip. It can be found that the fracture energy of the Zr-Al-Ni-Cu alloy is closely related with the development of shear bands during fracture.

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