Overview no. 100 Scalings in fracture probabilities for a brittle matrix fiber composite

Abstract This paper considers the statistical aspects of strengthening of a monolithic ceramic by the addition of continuous ceramic fibers in parallel. The failure process involves quasi-periodic matrix cracking, frictional sliding of the fibers in break zones, and fiber bridging of cracks in a global load-sharing framework. First we consider a “characteristic” bundle in the composite and develop its distribution for strength in terms of certain characteristic stress and length scales. We then consider the strength distribution for a chain arrangement of such bundles where failure of the weakest bundle triggers failure of the composite. The scale of load transfer among fibers in a bundle may be smaller than the full composite cross-section depending on such things as the stiffness of the matrix relative to the fibers and the spacing of periodic cracks. Substantial reductions in strength are predicted for smaller bundle sizes, but composite reliability is typically very high and the size effect very mild.

[1]  Anthony G. Evans,et al.  Overview no. 85 The mechanical behavior of ceramic matrix composites , 1989 .

[2]  K. Knowles,et al.  The One‐Dimensional Car Parking Problem and Its Application to the Distribution of Spacings between Matrix Cracks in Unidirectional Fiber‐Reinforced Brittle Materials , 1992 .

[3]  J. Gurland,et al.  Comparison of the statistics of two fracture modes , 1962 .

[4]  K. Prewo Tension and flexural strength of silicon carbide fibre-reinforced glass ceramics , 1986 .

[5]  S. Phoenix,et al.  Interfacial shear strength studies using the single‐filament‐composite test. Part II: A probability model and Monte Carlo simulation , 1989 .

[6]  H. E. Daniels,et al.  The maximum of a Gaussian process whose mean path has a maximum, with an application to the strength of bundles of fibres , 1989, Advances in Applied Probability.

[7]  B. W. Rosen,et al.  Tensile failure of fibrous composites. , 1964 .

[8]  S. L. Phoenix,et al.  The Chain-of-Bundles Probability Model for the Strength of Fibrous Materials II: A Numerical Study of Convergence , 1978 .

[9]  Bernard D. Coleman,et al.  On the strength of classical fibres and fibre bundles , 1958 .

[10]  S. L. Phoenix,et al.  Asymptotic Distributions for the Failure of Fibrous Materials Under Series-Parallel Structure and Equal Load-Sharing , 1981 .

[11]  William A. Curtin,et al.  Exact theory of fibre fragmentation in a single-filament composite , 1991 .

[12]  M. D. Thouless,et al.  Effects of pull-out on the mechanical properties of ceramic-matrix composites , 1988 .

[13]  K. Wetzig,et al.  Investigations on mechanical behaviour of brittle wear-resistant coatings I. Experimental results , 1983 .

[14]  William A. Curtin,et al.  THEORY OF MECHANICAL-PROPERTIES OF CERAMIC-MATRIX COMPOSITES , 1991 .

[15]  M. Sutcu,et al.  Weibull statistics applied to fiber failure in ceramic composites and work of fracture , 1989 .

[16]  P. Steif,et al.  A theory for the ultimate strength of a brittle-matrix composite , 1990 .

[17]  S. Leigh Phoenix,et al.  Clamp Effects in Fiber Testing , 1972 .

[18]  S. L. Phoenix,et al.  Recursions and limit theorems for the strength and lifetime distributions of a fibrous composite , 1987, Journal of Applied Probability.

[19]  L. N. McCartney,et al.  Statistical Theory of the Strength of Fiber Bundles , 1983 .

[20]  G. Gille Investigations on mechanical behaviour of brittle wear-resistant coatings II: Theory , 1984 .

[21]  J. G. Keer,et al.  On the theoretical average crack spacing in brittle matrix composites containing continuous aligned fibres , 1982 .

[22]  A. Evans,et al.  Failure Mechanisms in Ceramic‐Fiber/Ceramic‐Matrix Composites , 1985 .

[23]  S. L. Phoenix,et al.  The Chain-of-Bundles Probability Model For the Strength of Fibrous Materials I: Analysis and Conjectures , 1978 .

[24]  Reza Ghaffarian,et al.  Size effect and strength variability of unidirectional composites , 1984 .

[25]  O. Sbaizero,et al.  Effect of Interfaces on the Properties of Fiber‐Reinforced Ceramics , 1990 .

[26]  S. Phoenix Probabilistic inter-fiber dependence and the asymptotic strength distribution of classic fiber bundles , 1975 .

[27]  R. L. Smith,et al.  LOWER TAIL ANALYSIS OF THE DISTRIBUTION OF THE STRENGTH OF LOAD-SHARING SYSTEMS , 1983 .

[28]  Richard L. Smith The Asymptotic Distribution of the Strength of a Series-Parallel System with Equal Load-Sharing , 1982 .

[29]  S. Leigh Phoenix,et al.  The asymptotic strength distribution of a general fiber bundle , 1973, Advances in Applied Probability.