Prediction of Spring Rate and Initial Failure Load due to Material Properties of Composite Leaf Spring

복합재 판스프링의 재료특성에 따른 스프링 강성변화와 초기 파단하중 예측

  • Oh, Sung Ha (Maxoft Inc.) ;
  • Choi, Bok Lok (School of Mechanical and Automotive Engineering, Gangneung-Wonju Nat'l Univ.)
  • 오성하 (맥소프트(주) 기술연구소) ;
  • 최복록 (강릉원주대학교 기계자동차공학부)
  • Received : 2014.05.27
  • Accepted : 2014.08.25
  • Published : 2014.12.01


This paper presented analysis methods for adapting E-glass fiber/epoxy composite (GFRP) materials to an automotive leaf spring. It focused on the static behaviors of the leaf spring due to the material composition and its fiber orientation. The material properties of the GFRP composite were directly measured based on the ASTM standard test. A reverse implementation was performed to obtain the complete set of in-situ fiber and matrix properties from the ply test results. Next, the spring rates of the composite leaf spring were examined according to the variation of material parameters such as the fiber angles and resin contents of the composite material. Finally, progressive failure analysis was conducted to identify the initial failure load by means of an elastic stress analysis and specific damage criteria. As a result, it was found that damage first occurred along the edge of the leaf spring owing to the shear stresses.


Leaf Spring;Spring Rate;GFRP;FEM;Progressive Failure Analysis


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