• 제목/요약/키워드: energy material

검색결과 8,066건 처리시간 0.038초

전위 및 공공을 고려한 고변형률 변형에 대한 재료 시뮬레이션 (A Material Simulation of High-Strain-Rate Deformation with Dislocations and Vacancies)

  • 최덕기;유한규
    • 대한기계학회논문집A
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    • 제28권9호
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    • pp.1306-1313
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    • 2004
  • This paper addresses a theoretical approach to calculate the amount of the stored energy during high strain-rate deformations using atomistic level simulation. The dynamic behavior of materials at high strain-rate deformation are of great interest. At high strain-rates deformations, materials generate heat due to plastic work and the temperature rise can be significant, affecting various properties of the material. It is well known that a small percent of the energy input is stored in the material, and most of input energy is converted into heat. However, microscopic analysis has not been completed without construction of a material model, which can simulate the movement of dislocations and vacancies. A major cause of the temperature rise within materials is traditionally credited to dislocations, vacancies and other defects. In this study, an atomistic material model for FCC such as copper is used to calculate the stored energy.

Silicone 봉지재를 이용한 태양광 모듈 제조 공정 및 평가에 대한 연구 (The study on evaluation for PV module development using the silicone encapsulation)

  • 정인성;이범수;양오봉;강성환;김종일
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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    • pp.137-142
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    • 2011
  • Individual solar cells must be connected together to give the appropriate current and voltage levels and they must also be protected from damage by the environment. [1] PV module consists of a glass/ polymer encapsulation/ solar cell string/ polymer encapsulation/ back sheet. Usually, encapsulation materials is used EVA(ethylene vinyl acetate), PVB(polyvinyl butyral), PO(polyolefin)sheet. This study is about fabrication of module using silicone material instead of above them. We got to know advantage that is fabrication time and efficiency of modules.

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On the analysis of delamination in multilayered inhomogeneous rods under torsion

  • Rizov, Victor I.
    • Coupled systems mechanics
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    • 제8권5호
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    • pp.377-391
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    • 2019
  • The present paper is focused on analyzing the delamination of inhomogeneous multilayered rods of circular cross-section loaded in torsion. The rods are made of concentric longitudinal layers of individual thickness and material properties. A delamination crack is located arbitrary between layers. Thus, the internal and external crack arms have circular and ring-shaped cross-sections, respectively. The layers exhibit continuous material inhomogeneity in radial direction. Besides, the material has non-linear elastic behavior. The delamination is analyzed in terms of the strain energy release rate. General solution to the strain energy release rate is derived by considering the energy balance. The solution is applied to analyze the delamination of cantilever rod. For verification, the strain energy release rate is derived also by considering the complementary strain energy.

Failure Analysis of a Ball in the Nuclear Fuel Exchanger

  • Kim, H.P.;Kim, D.J.;Hwang, S.S.;Joung, M.K.;Lim, Y.S.;Kim, J.S.
    • Corrosion Science and Technology
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    • 제4권5호
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    • pp.211-216
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    • 2005
  • Failure analysis of the latch ram ball and the C-ram ball with the trade name AFBMA Gr. 50 Colmonoy No. 6, has been performed to identify the root cause of the failure. The study required the extraction of the both failed and normal balls from the nuclear fuel exchanger. Microstructures of both balls were examined after polishing and etching. Breaking tests of both the ball revealed similarity in cleavage surfaces. Fracture surfaces of both failed ball and normal ball after breaking test were examined with SEM and EDX. Microstructure of the ball revealed an austenite phase with coarse Cr rich precipitate. Indented marks observed on the surface of the failed ball are believed to be produced by overloading. In the light of the afore mentioned observations and studies, the failure mechanism of the ball in nuclear fuel exchanger seem to be caused by impact or mechanical overloading on ball.

고무의 피로 수명 예측을 위한 찢김에너지 수식화 (Estimation of Tearing Energy for Fatigue Life Prediction of Rubber Material)

  • 김호;김헌영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.172-177
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    • 2004
  • Fatigue life prediction is based on fracture mechanics and database which is established from experimental method. Rubber material also uses the same way for fatigue life prediction. But the absence of standardization of rubber material, various way of composition by each rubber company and uncertainty of fracture criterion makes the design of fatigue life by experimental method almost impossible. Tearing energy which has its origin in energy release rate is evaluated as fracture criterion of rubber material and the applicability of fatigue life prediction method are considered. The system of measuring tearing energy using the principal of virtual crack extension method and fatigue life prediction by the minimum number of experiments are proposed.

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