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A Study on the Prediction of Elastic Modulus in Short Fiber Composite Materials

단섬유 복합재료의 탄성계수 예측에 관한 연구

  • 김홍건 (전주대학교 기계공학과)
  • Published : 2005.02.01

Abstract

Theoretical efforts are performed to extend the formulation of NSLT(New Shear Lag Theory) for the prediction of the elastic modulus in short fiber composite. The formulation is based on the elastic stress transfer considering the stress concentration effects influenced by elastic modulus ratio between fiber and matrix. The composite modulus, thus far, is calculated by changing the fiber aspect ratio and volume fraction. It is found that the comparison with FEA(Finite Element Analysis) results gives a good agreement with the present theory (NSLT). It is also found that the NSLT is more accurate than the SLT(Shear Lag Theory) in short fiber regime when compared by FEA results. However, The modulus predicted by NSLT becomes similar values that of SLT when the fiber aspect ratio increases. Finally, It is shown that the present model has the capability to predict the composite modulus correctly in elastic regime.

Keywords

Composites;Elastic Modulus;FEA;Fiber Aspect Ratio;Fiber Volume Fraction;SLT;NSLT

References

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