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Viscoelasticity of engineering materials
PII: SO9KM695@@00025-4
ELSEVIER
NDT&Z International, Vol. 29, No. 4, pp. 241, 1996 Copyright 0 1996 Elsevier Science Ltd Printed in Great Britain. All rights reserved 0963-8695/96 $15.00 + 0.00
FBook review Viscoelasticity Y. M. Haddad Chapman and Hall, 1995,378 As suggested by the title, this book is primarily intended for stress analysis and modelling of the mechanical behaviour of materials, especially viscoelastic solids such as polymers and polymeric based composites. This book provides a unified and complete presentation of the theory of viscoelastic solids. Of particular interest to NDE is probably the detailed coverage on (stress) wave propagation in linear or nonlinear viscoelastic solid media. The book consists of ten chapters and four appendixes, covering the fundamentals and experimental validations. Chapter 1 provides a brief introduction to the mechanics framework, within which the book is constructed. Basic theories on linear viscoelasticity are outlined in Chapter 2, with emphasis on the modelling of various isothermal behaviour, for example creep, relaxation. In this chapter simple one-dimensional models, such as the Maxwell and the Kelvin model, are first introduced, and then the more general models. In Chapter 3 these formulations are extended to include the possibility of characterizing the linear viscoelastic behaviour of materials under dynamic loading or deformation.
of engineering pp, ISBN O-42-59030-1,
materials
f69
Since structures are in general subjected to multiaxial stresses, the one-dimensional formulations introduced in Chapter 2 are further extended to include the generalization of the formulations to the three-dimensional case. This involves replacing the onedimensional constitutive relationships by their corresponding tensorial equivalents. To reflect the effect of temperature on the viscoelastic behaviour materials, a chapter, Chapter 5, is devoted to the problem of thermoviscoelasticity. Chapter 6 of this book deals with the nonlinear aspect of viscoelasticity and the associated analytical modelling. Having introduced the theories and analytical models, the next chapter, Chapter 7, is devoted to the identification and numerical characterization of the formulae. In particular, some typical values for the material parameters are included in this chapter. Chapter 8 presents a detailed account of the propagation of waves in elastic and viscoelastic solids, stress waves in particular. To solve the wave propagation problem, the constitutive equation for a particular material must be combined with the equations of motion. Due to the integrodifferential terms in the equations
241
and the time dependency of the viscoelastic material functions involved, the solutions are complicated, even in simple cases. The treatment presented in this chapter should be very helpful in this regard. For a real structure, the boundary condition is also important in determining the actual stress-strain state. In recognition of this, Chapter 9 of the book deals with the formulation and subsequently the solution of the boundary value problems in viscoelasticity. Examples include torsional twisting of a linear viscoelastic cylinder and spherical indentor on a viscoelastic halfspace. The remaining chapter of the book outlines the development in relating the microscopic effects to viscoelasticity. Throughout the book is clearly written and well illustrated. The book is directly relevant to NDE of viscoelastic materials, such as polymers, but to a lesser extent to those people concerned with metals. Chun H. Wang Aeronautical and Maritime Research Laboratory, Melbourne, Australia
ELSEVIER
NDT&Z International, Vol. 29, No. 4, pp. 241, 1996 Copyright 0 1996 Elsevier Science Ltd Printed in Great Britain. All rights reserved 0963-8695/96 $15.00 + 0.00
FBook review Viscoelasticity Y. M. Haddad Chapman and Hall, 1995,378 As suggested by the title, this book is primarily intended for stress analysis and modelling of the mechanical behaviour of materials, especially viscoelastic solids such as polymers and polymeric based composites. This book provides a unified and complete presentation of the theory of viscoelastic solids. Of particular interest to NDE is probably the detailed coverage on (stress) wave propagation in linear or nonlinear viscoelastic solid media. The book consists of ten chapters and four appendixes, covering the fundamentals and experimental validations. Chapter 1 provides a brief introduction to the mechanics framework, within which the book is constructed. Basic theories on linear viscoelasticity are outlined in Chapter 2, with emphasis on the modelling of various isothermal behaviour, for example creep, relaxation. In this chapter simple one-dimensional models, such as the Maxwell and the Kelvin model, are first introduced, and then the more general models. In Chapter 3 these formulations are extended to include the possibility of characterizing the linear viscoelastic behaviour of materials under dynamic loading or deformation.
of engineering pp, ISBN O-42-59030-1,
materials
f69
Since structures are in general subjected to multiaxial stresses, the one-dimensional formulations introduced in Chapter 2 are further extended to include the generalization of the formulations to the three-dimensional case. This involves replacing the onedimensional constitutive relationships by their corresponding tensorial equivalents. To reflect the effect of temperature on the viscoelastic behaviour materials, a chapter, Chapter 5, is devoted to the problem of thermoviscoelasticity. Chapter 6 of this book deals with the nonlinear aspect of viscoelasticity and the associated analytical modelling. Having introduced the theories and analytical models, the next chapter, Chapter 7, is devoted to the identification and numerical characterization of the formulae. In particular, some typical values for the material parameters are included in this chapter. Chapter 8 presents a detailed account of the propagation of waves in elastic and viscoelastic solids, stress waves in particular. To solve the wave propagation problem, the constitutive equation for a particular material must be combined with the equations of motion. Due to the integrodifferential terms in the equations
241
and the time dependency of the viscoelastic material functions involved, the solutions are complicated, even in simple cases. The treatment presented in this chapter should be very helpful in this regard. For a real structure, the boundary condition is also important in determining the actual stress-strain state. In recognition of this, Chapter 9 of the book deals with the formulation and subsequently the solution of the boundary value problems in viscoelasticity. Examples include torsional twisting of a linear viscoelastic cylinder and spherical indentor on a viscoelastic halfspace. The remaining chapter of the book outlines the development in relating the microscopic effects to viscoelasticity. Throughout the book is clearly written and well illustrated. The book is directly relevant to NDE of viscoelastic materials, such as polymers, but to a lesser extent to those people concerned with metals. Chun H. Wang Aeronautical and Maritime Research Laboratory, Melbourne, Australia