• 제목/요약/키워드: Fe-Si alloy

검색결과 412건 처리시간 0.03초

자동차 부품용 내열 알루미늄 합금의 고온 피로 변형 거동 (High Temperature Fatigue Deformation Behavior of Automotive Heat Resistant Aluminum Alloys)

  • 박종수;성시영;한범석;정창렬;이기안
    • 대한금속재료학회지
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    • 제48권1호
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    • pp.28-38
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    • 2010

  • High temperature high cycle and low cycle fatigue deformation behavior of automotive heat resistant aluminum alloys (A356 and A319 based) were investigated in this study. The microstructures of both alloys were composed of primary Al-Si dendrite and eutectic Si phase. However, the size and distribution for eutectic Si phase varied: a coarse and inhomogeneous distributed was observed in alloy B (A319 based). A brittle intermethallic phase of ${\alpha}-Fe\;Al_{12}(Fe,Mn)_3Si_2$ was detected only in B alloy. Alloy B exhibited high fatigue life only under a high stress amplitued condition in the high cycle fatigue results, whereas alloy A showed high fatigue life when stress was lowered. With regard to the low-cycle fatigue result ($250^{\circ}C$) showing higher fatigue life as ductility increased, alloy A demonstrated higher fatigue life under all of the strain amplitude conditions. Fractographic observations showed that large porosities and pores near the outside surface could be the main factor in the formation of fatigue cracks. In alloy B. micro-cracks were formed in both the brittle intermetallic and coarse Si phasese. These micro-cracks then coalesced together and provided a path for fatigue crack propagation. From the observation of the differences in microstructure and fractography of these two automotive alloys, the authors attempt to explain the high-temperature fatigue deformation behavior of heat resistant aluminum alloys.

  • https://doi.org/10.3365.KJMM.2010.48.01.028 인용 KSCI

MAGNETIC PROPERTIES OF GRANULAR Fe-SiO FILMS

  • Furubayashi, Takao;Nakatani, Isao
    • 한국자기학회지
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    • 제5권5호
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    • pp.474-477
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    • 1995

  • Granular Fe-SiO films were prepared by co-evaporating in a vacuum. Magnetic properties of the films were investigated by $M\"{o}ssbauer$ and magnetization measurments. The $M\"{o}ssbauer$ data suggest that the films consist of amorphous Fe-Si alloy particles with the size of nanometers. Superparamagnetic magnetization curves were well reproduced by considering the distribution of particle size and the magnetic dipole interaction between particles as the mean field.

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