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KSME Journal

, Volume 10, Issue 1, pp 49–56 | Cite as

Ultimate strength prediction of continuous fiber-reinforced brittle matrix composites

  • Chongdu Cho
Article
  • 78 Downloads

Abstract

A model to predict ultimate strength of continuous fiber-reinforced brittle matirix composites has been developed. A statistical theory for the strength of the uniaxially fiber-reinforced brittle matrix composite is presented. Material of matrix is assumed to be homogeneous and isotropic, so that the strength of material is anywhere constant, whilst that of fiber is considered to show Weibull statistical distribution. The theory may be utilized to optimize the biaxial and multidirectional tensile strength properties of laminated materials. The composite strength is estimated by assuming no interacting matrix cracks. The frictional shear stress caused by bridging fibers is involved in the strength computation. The predicted strength is compared to experimental results with LAS-Glass/Nicalon fiber composite.

Key Words

Brittle Matrix Composite Weibull Statistics Tensile Strength Interfacial Friction Fibers 

Nomenclature

df

Fiber diameter

E

Elastic modulus

\(G_{\delta z_i } \left( {\sigma _i } \right)\)

Probability that the element δZ i fractures subjected to the stress less than σ i

H

Fiber specimen length

<h>

Average fracture distance

l

Slip zone length

m

Weibull modulus

P

Probability of failure

S0

Strength scaling parameter; fiber mean strength (m=∞)

v

Volume fraction

α

Dimension factor

α0

Normalizing parameter

η

Parameter defined by 4τ/d f

σ

Normal stress

σh

Fiber specimen failure stress

σi

Fiber stress at a distancez i

σULT

Ultimate strength

τ

Interfacial shear stress

ξ

Parameter defined by σ m /S 0

Subscripts

c

Composite

f

Fiber

m

Matrix

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References

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Copyright information

© The Korean Society of Mechanical Engineers (KSME) 1996

Authors and Affiliations

  • Chongdu Cho
    • 1
  1. 1.iASMELab, Department of Mechanical EngineeringInha UniversityInchonKorea

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