Influence of fiber architecture on the inelastic response of metal matrix composites

Abstract This three-part paper focuses on the effect of fiber architecture (i.e. shape and distribution) on the elastic and inelastic response of unidirectionally reinforced metal matrix composites (MMCs). The first part provides an annotated survey of the literature; it is presented as an historical perspective dealing with the effects of fiber shape and distribution on the response of advanced polymeric matrix composites and MMCs. A summary of the state of teh art will assist in defining new directions in this quickly reviving area of research. The second part outlines a recently developed analytical micromechanics model that is particularly well suited for studying the influence of these effects on the response of MMCs. This micromechanics model, referred to as the generalized method of cells (GMC), can predict the overall inelastic behavior of unidirectional, multiphase composites, given the properties of the constituents. The model is also general enough to predict the response of unidirectional composites that are reinforced by either continuous or discontinuous fibers, with different inclusion shapes and spatial arrangements, in the presence of either perfect or imperfect interfaces and/or interfacial layers. Recent developments on this promising model, as well as directions for future enhancements of the model's predictive capability, are included. Finally, the third part provides qualitative results generated by using GMC for a representative titanium matrix composite system, SCS-6/TIMETAL 21S. The results presented correctly demonstrate the relative effects of fiber arrangement and shape on the longitudinal and transverse stress-strain and creep behavior of MMCs, with both strong and weak fiber/matrix interfacial bonds. Fiber arrangements included square, square-diagonal, hexagonal and rectangular periodic arrays, as well as a random array. The fiber shapes were circular, square, and cross-shaped cross-sections. The effect of fiber volume fraction on the stress-strain response is also discussed, as is the thus-far poorly documented strain rate sensitivity effect. In addition to the well-documented features of the architecture-dependent behavior of continuously reinforced two-phase MMCs, new results are presented about continuous multiphase internal architectures. Specifically, the stress-strain and creep responses of composites with different size fibers and different internal arrangements and bond strengths are investigated; the aim was to determine the feasibility of using this approach to enhance the transverse toughness and creep resistance of titanium matrix composites (TMCs).

[1]  K. Osamura,et al.  Tensile strength of fibre-reinforced metal matrix composites with non-uniform fibre spacing , 1989 .

[2]  Zhigang Suo,et al.  Matrix cracking in intermetallic composites caused by thermal expansion mismatch , 1991 .

[3]  A. Mueller A finite element method for microstructural analysis , 1994 .

[4]  Donald F. Adams,et al.  The Influence of Random Filament Packing on the Transverse Stiffness of Unidirectional Composites , 1969 .

[5]  Steven M. Arnold,et al.  On the thermodynamic framework of generalized coupled thermoelastic-viscoplastic-damage modeling , 1994 .

[6]  Donald F. Adams,et al.  Inelastic Analysis of a Unidirectional Composite Subjected to Transverse Normal Loading , 1970 .

[7]  Raymond L. Foye,et al.  Theoretical Post-Yielding Behavior of Composite Laminates Part II-Inelastic Macromechanics , 1973 .

[8]  Shankar Mall,et al.  Micromechanical Relations for Fiber-Reinforced Composites Using the Free Transverse Shear Approach , 1993 .

[9]  John C. Halpin,et al.  Primer on Composite Materials Analysis , 1984 .

[10]  K. P. Walker,et al.  Microstress analysis of periodic composites , 1991 .

[11]  Boundary Point Least Squares Analysis of the Free Edge Effects in Some Unidirectional Fiber Composites , 1971 .

[12]  B. Lerch,et al.  Tensile Deformation of SiC/Ti-15-3 Laminates , 1993 .

[13]  Sia Nemat-Nasser,et al.  On composites with periodic structure , 1982 .

[14]  D. J. Wilkins,et al.  Constituent scale and property effects on fibre — matrix debonding and pull-out , 1991 .

[15]  Steven M. Arnold,et al.  A fully associative, nonisothermal, nonlinear kinematic, unified viscoplastic model for titanium alloys , 1996 .

[16]  S. Shtrikman,et al.  A variational approach to the theory of the elastic behaviour of multiphase materials , 1963 .

[17]  M. Paley,et al.  Micromechanical analysis of composites by the generalized cells model , 1992 .

[18]  P. Wright,et al.  Micromechanical modeling of fiber/matrix interface effects in transversely loaded SiC/Ti-6-4 metal matrix composites , 1991 .

[19]  George Z. Voyiadjis,et al.  Damage in composite materials , 1993 .

[20]  S. Mall,et al.  Micromechanical analysis of metal matrix composite laminates with fiber/matrix interfacial damage , 1994 .

[21]  T. Lin,et al.  Elastic-Plastic Analysis of Unidirectional Composites , 1972 .

[22]  Jacob Aboudi,et al.  Constitutive equations for elastoplastic composites with imperfect bonding , 1988 .

[23]  A. Saleeb,et al.  A Modeling Investigation of Thermal and Strain Induced Recovery and Nonlinear Hardening in Potential Based Viscoplasticity , 1993 .

[24]  Their Composites,et al.  Composite Materials: Fatigue and Fracture , 1992 .

[25]  M. Wisnom Factors Affecting the Transverse Tensile Strength of Unidirectional Continuous Silicon Carbide Fibre Reinforced 6061 Aluminum , 1990 .

[26]  H. S. Schwartz,et al.  Fundamental Aspects of Fiber Reinforced Plastic Composites. , 1968 .

[27]  C. Bigelow The Effects of Uneven Fiber Spacing on Thermal Residual Stresses in a Unidirectional SCS-6/Ti-15-3 Laminate , 1992 .

[28]  Jacob Aboudi,et al.  Micromechanical Analysis of Composites by the Method of Cells , 1989 .

[29]  S. Suresh,et al.  Plastic deformation of continuous fiber-reinforced metal-matrix composites: Effects of fiber shape and distribution , 1990 .

[30]  D. Salinas,et al.  Initial Yield Surface of a Unidirectionally Reinforced Composite , 1972 .

[31]  Zvi Hashin,et al.  On elastic behaviour of fibre reinforced materials of arbitrary transverse phase geometry , 1965 .

[32]  Zvi Hashin,et al.  Theory of fiber reinforced materials , 1972 .

[33]  Steven M. Arnold,et al.  A Fully Associative, Nonlinear Kinematic, Unified Viscoplastic Model for Titanium-Based Matrices , 1996 .

[34]  Aboudi Micromechanical analysis of thermo-inelastic multiphase short-fiber composites. Final report , 1994 .

[35]  C. Chamis,et al.  Critique on Theories Predicting Thermoelastic Properties of Fibrous Composites , 1968 .

[36]  Donald F. Adams,et al.  Longitudinal Shear Loading of a Unidirectional Composite , 1967 .

[37]  J. Aboudi Mechanics of composite materials - A unified micromechanical approach , 1991 .

[38]  K. Osamura,et al.  Stress disturbance due to broken fibres in metal matrix composites with non-uniform fibre spacing , 1989 .

[39]  R. Mehan,et al.  Failure modes in composites. II , 1974 .

[40]  R. MacKay Effect of fiber spacing on interfacial damage in a metal matrix composite , 1990 .

[41]  B. Majumdar,et al.  Inelastic deformation of metal matrix composites: Plasticity and damage mechanisms, part 2. Final Report , 1992 .

[42]  S. Nemat-Nasser,et al.  Micromechanics: Overall Properties of Heterogeneous Materials , 1993 .

[43]  Steven M. Arnold,et al.  Micromechanics Analysis Code (MAC). User Guide: Version 2.0 , 1994 .

[44]  G. J. Dvorak,et al.  Generalized Initial Yield Surfaces for Unidirectional Composites , 1974 .

[45]  N. Pagano,et al.  The full-cell cracking mode in unidirectional brittle-matrix composites , 1993 .

[46]  Z. Hashin,et al.  The Elastic Moduli of Fiber-Reinforced Materials , 1964 .

[47]  Donald F. Adams,et al.  Transverse Normal Loading of a Unidirectional Composite , 1967 .

[48]  M. S. Madhava Rao,et al.  Yielding in Unidirectional Composites Under External Loads and Temperature Changes* , 1973 .

[49]  Subra Suresh,et al.  Effects of thermal residual stresses and fiber packing on deformation of metal-matrix composites , 1993 .

[50]  C. Lissenden,et al.  Stiffness degradation of SiC/Ti tubes subjected to biaxial loading , 1994 .

[51]  On the finite element implementation of the generalized method of cells micromechanics constitutive model , 1995 .

[52]  Franz G. Rammerstorfer,et al.  Some simple models for micromechanical investigations of fiber arrangement effects in MMCs , 1993 .

[53]  Subra Suresh,et al.  Deformation of metal-matrix composites with continuous fibers: geometrical effects of fiber distribution and shape , 1991 .

[54]  U. F. Zackay High-strength Materials , 1965 .

[55]  J. Aboudi,et al.  Thermo-inelastic response of functionally graded composites , 1995 .

[56]  K. P. Walker,et al.  Nonlinear mesomechanics of composites with periodic microstructure , 1989 .

[57]  J. Aboudi,et al.  Elastic response of metal matrix composites with tailored microstructures to thermal gradients , 1994 .

[58]  Steven M. Arnold,et al.  Response of functionally graded composites to thermal gradients , 1994 .