• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2004년도 제35차 추계학술대회 및 제2회 HVEM 이용자 워크샵
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• pp.61-63
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• 2004

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2011년도 임시총회 및 하계학술연구발표회
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• pp.150-151
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• 2011

• 기계와재료
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• 제17권3호통권65호
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• pp.69-79
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• 2005

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 춘계학술발표대회
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• pp.39.2-39.2
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• 2009

벌크 비정질 합금 및 공정 조직 합금은 기존의 상용 합금들에 비해 월등히 높은 강도 및 탄성 변형 한계를 나타내며, 고내식, 고마모 특성 등 매우 독특하며 유용한 특성을 보인다. 하지만 상온에서 지극히 제한적인 연성으로 인하여 우수한 특성에도 불구하고 많은 분야에 활용이 되지 못하고 있다. 이러한 단점을 보완하기 위하여 미세조직의 복합화를 통한 연성 부여에 대한 연구가 활발히 진행이 되고 있다. 본 연구에서는 Fe- 합금을 선택하고 비정질 형성능 향상을 위하여 Si를 첨가하였고 그 조성에 따른 미세조직 변화 및 기계적 특성을 관찰하였다. 기계적 특성 평가를 위해 압축시험을 실시하였으며, 미세조직 및 상분석을 통하여 기계적 특성과의 관계에 대해 조사를 하였다. 이때 미세조직 및 상분석 관찰을 위하여 TEM, XRD, SEM을 사용하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 춘계학술대회 논문집
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• pp.107-108
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• 2008

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2005년도 추계학술강연 및 발표대회강연 및 발표논문 초록집
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• pp.106-106
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• 2005

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 추계총회 및 학술대회 논문집
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• pp.54-54
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• 2012

• 한국레이저가공학회:학술대회논문집
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• 한국레이저가공학회 2005년도 춘계학술발표대회 논문집
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• pp.9-14
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• 2005

• 한국정밀공학회지
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• 제23권4호
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• pp.153-161
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• 2006

Micro-forming is a suited technology to manufacture very small metallic parts(several $mm{\sim}{\mu}m$). Micro-forming of $Zr_{62}Cu_{17}Ni_{13}Al_8$ bulk metallic glass(BMG) as a candidate material for this developing process are feasible at a relatively low stress in the supercooled liquid state without any crystallization during hot deformation. In this study, micro- formability of a representative bulk metallic glass, $Zr_{62}Cu_{17}Ni_{13}Al_8$. was investigated for micro-forging of U-shape pattern. Micro-formability was estimated by comparing $R_f$ values ($=A_f/A_g$), where $A_g$ is cross-sectional area of U groove, and $A_f$ the filled area by material. Micro-forging process was simulated and analyzed by applying finite element method. FEM simulation results showed reasonable agreement with the experimental results when the material properties and simulation conditions such as top die speed, remeshing criteria and boundary conditions were tightly controlled. The micro-formability of $Zr_{62}Cu_{17}Ni_{13}Al_8$ was increased with increasing load and time in the temperature range of the supercooled liquid state. Also, FEM simulation using a commercial software, DEFORM was confirmed to be applicable for the optimization of micro-forming process.

• Tribology and Lubricants
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• 제30권5호
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• pp.295-302
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• 2014

The tribological behavior of an Fe-based bulk amorphous alloy while sliding against a AISI 304 disc is investigated using a unidirectional pin-on-disc type tribometer in dry and distilled water environments. The rod-shaped bulk pins are fabricated by suction casting. The crystallinities of the bulk amorphous alloys before and after the friction tests are determined by X-ray diffraction. The friction coefficient and specific wear rate of the amorphous pin in the water environment are found to be twice and thrice as much as in the dry environment at a low applied pressure, respectively. However, at a higher pressure, the friction coefficient and specific wear rate are 0.4 and 1.02 mg/(Nm/s), respectively, in the water environment. A microstructure analysis shows that the worn surface of the alloy is characterized by delamination from the smooth friction surface, and thus delamination is the main wear mechanism during the friction test in dry sliding environment. In contrast, brittle fracture morphologies are apparent on the friction surface formed in distilled water environment. For the sample tested at a lower sliding speed, the XPS data from the oxide layer are similar to those of the pure element with weak suboxide peaks. For higher sliding speeds, all the main sharp peaks representing the core level binding energies are shifted to the oxide region.