• 제목/요약/키워드: 마찰 변태 구조

검색결과 2건 처리시간 0.014초

핵연료 봉의 마찰변태구조 관찰과 프레팅 마멸 특성 (Observation of Tribologically Transformed Structures and fretting Wear Characteristics of Nuclear Fuel Cladding)

  • 김경호;이민구;이창규;위명용;김흥회
    • 대한기계학회논문집A
    • /
    • 제26권12호
    • /
    • pp.2581-2589
    • /
    • 2002
  • In this research, fretting tests were conducted in air to investigate the wear characteristics of fuel cladding materials with the fretting parameters such as normal load, slip amplitude, frequency and the number of cycles. A high frequency fretting wear tester was designed for this experiment by KAERI. After the experiments, the wear volume and the shape of wear contour were measured by the surface roughness tester. Tribologically transformed structures(TTS) were analysed by means of optical and scanning electron microscopes to identify the main wear mechanisms. The results of this study showed that the wear volume were increased with increasing slip amplitude, and the shape of wear contour was transformed V-type to W-type. Also, it was found that the critical slip amplitude was 168${\mu}{\textrm}{m}$. These phenomena mean that wear mechanism transformed partial slip to gross slip to accelerate wear volume. The wear depth increased with an increase of friction coefficient due to increase of normal load and frequency. The fretting wear mechanisms were believed that, after adhesion and surface plastic deformation occurred by relative sliding motion on the contact between two specimens, TTS creation was induced by surface strain hardening and wear debris were detached from the contact surface which were produced by the micro crack propagation and creation.

CFUBM 시스템으로 합성한 CrN / CrAlN 초격자 박막의 마찰 특성 (Tribological properties of CrN / CrAlN superlattice thin films by CFUBMS)

  • 변태준;김연준;한전건
    • 한국표면공학회:학술대회논문집
    • /
    • 한국표면공학회 2007년도 추계학술대회 논문집
    • /
    • pp.130-131
    • /
    • 2007
  • 초고경도 박막을 얻기 위해 질화물을 이용한 CrN / CrAlN 초격자 박막을 CFUBM 시스템을 통해 합성하였다. 초격자 박막의 각층의 두께 (${\lambda}$)는 기판의 회전 속도를 이용하여 제어하여 4.4 에서 44.1 nm 까지 합성하였다. 박막의 결정구조 및 미세구조를 분석하기 위하여 고분해능 X선 회절 분석기 (HR-XRD)를 이용하였으며, 박막의 기계적 성질은 나노 인덴터와 ball on disk tester를 통해 분석하였다. CrN / CrAlN 초격자 박막은 각층의 두께 (${\lambda}$)에 따라 28.77 GPa에서 31.97 GPa의 경도 값을 나타내었으며, 미세구조와 기계적 특성이 변화를 관찰할 수 있었다.

  • PDF