• 제목/요약/키워드: Pulsed vacuum arc

검색결과 11건 처리시간 0.017초

Laser Ablation법에 의한 ZrVFe 합금 나노분말 제조 (Preparation of ZrVFe Nano Powders by Laser Ablation)

  • 길대섭;서용재;장희동;이재천;송창빈;김원백
    • 한국재료학회지
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    • 제15권4호
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    • pp.257-262
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    • 2005
  • Nano-sized ZrVFe alloy powders were prepared by the ablation of powder compact in alcobol using a Nd-YAG pulsed Laser. The $Zr_{57}V_{35.}8Fe_{7.2}$ alloy commercially designated as ST707 has long been known as the ideal solution for various vacuum applications. The target for the ablation was sintered pellets of $Zr_{57}V_{35.}8Fe_{7.2}$ alloy powder. The alloy was prepared by arc melting and Hydride-DeHydride method. The ablated powders were mostly circular having fairly large size distribution smaller than 200 nm in all cases. The X-ray diffraction study revealed that the ablated alloy retained the crystal structure of the target alloy. Nevertheless, Fe and V contents in the ablated powder were lower than those in the target alloy. This was believed to result from the high vapour pressures of Fe and V compared to that of Zr. The size of the powders ablated at high energy fluence tends to decrease due at least partly to the breakdown of previously made ones.