Synopses & Reviews
This book contains geometrical and thermodynamical issues indispensable for development of a rational theory of thermoviscoplasticity. Geometrical picture of coupled thermomagnetomechanical histories of damaged solids is built both by means of Kroener's incompatibility approach as well by Eshelbian implanting eigenstrains. Duality of Euclidean anholonomic and non-Euclidean natural state space is also outlined in this book. Damaged inelastic materials of differential type, discrete and infinitesimal memory are obtained from principle of thermo-inelastic memory. Issue of plastic spin is considered. Postulate of minimal plastic work and corresponding non-associativity 4-tensor are then used to show whether associativity of flow rule holds. Postulates of Drucker, Iliushin and Hill are discussed. Thermodynamics of inelasticity is extensively discussed in classical, rational, extended and endochronic version with account to statistical thermodynamics. A non-steady aging is used in endochronic thermodynamics to cover creep-pasticity coupled inelastic histories. Multiaxial dynamic experiments with cylindrical, ``bichierino and cruciform specimen from austenitic stainless steels are analyzed. Quasi-rate independence and Rabotnov's plastic delay is combined with tensor representation. Inelastic ferromagnetics are treated by means of extended as well endochronic thermodynamics. For low cycle fatigue the experimentally observed displacement of magnetic induction history with respect to stress history is analyzed. Self consistent method applied to inelastic polycrystals is based on constrained micro-rotations and free meso-rotations. A special attention is devoted to slight disorder of polycrystal grains. The theory is confronted with classical J2-theory. Different inelastic multiaxial stress histories are analyzed and corresponding active slip systems determined. For numerical results micro quasi rate independence and relaxed Taylor's model are used. The theory of inelastic micromorphic polycrystals with couple stresses needs a very small number of necessary material constants. Nonproportionality of strain history as well as intergranular continuity are related to antisymmetry of stress tensor. Key topics: * Includes a detailed description of the geometry of thermo-deformation with local evolving natural state configuration * Provides a comparative review of various models of thermodynamics (classical, rational, endochronic, statistical) with special approach to inelastic high speed histories * Introduces quasi-rate independence and its application to plastic waves, ratcheting, and diffuse localization * Explores the sensor representation approach to thermo-inelastic coupled fields connected to a generalized associativity of flow rule as well as a comparison with the J2-approach * Examines micromechanics based on micro grain approach leading to reduced number of material constants * Provides biaxial cruciform specimen Hopkinson bar results * Reexamines the Hill's yield function for nonproportional stress-thermo-strain histories This book is intended for material science experts and professionals interested in impact experiments, continuum mechanics researchers, engineers in research institutes and graduate and Phd students aiming to apply FEM to calculate strength of structures at time varying thermo-mechanical excitations.
This comprehensive monograph is the first to treat an important and challenging subject in mechanics, namely, the thermomechanics of viscoplasticity. This entails an examination of the geometrical and thermodynamical properties of mechanical behavior of metals and many polymeric and paste-like materials which are indispensable for developing a rational theory of viscoplasticity.
Key features and topics include:
- a comparative review of various models of thermodynamics including classical, rational, statistical, and endochronic, with a special approach to inelastic high speed histories;
- a tensor representation approach to thermo-inelastic coupled fields connected to a generalized associativity of flow rule; includes a comparison with the J2 approach;
- discussion of Drucker, Iliushin, and Hill postulates; special attention devoted to the slight disorder of polycrystal grains;
- quasi-rate independence and its application to plastic waves, ratcheting and diffuse localization;
- micromechanics based on the micro grain approach leading to a reduced number of material constants;
- especially useful to the emergent field of biomechanics.
This book is intended for researchers as well as Ph.D. students in the fields of material science and continuum mechanics. Designers and engineers in the field of metal forming, car body calculations, airplane designers, and anyone involved in the design of large scale industrial parts, will also find this book highly useful. Additionally, the concepts and results illustrated in Thermomechanics of Viscoplasticity are readily applicable to therapidly developing field of biomechanics.
This work examines the geometrical and thermodynamical properties of mechanical behavior of metals and many polymeric and paste-like materials which are indispensable for developing a rational theory of viscoplasticity. The book is intended for researchers as well as Ph.D. students in the fields of material science and continuum mechanics. Anyone involved in the design of large scale industrial parts will also find this book highly useful. The concepts and results illustrated in this work are readily applicable to the rapidly developing field of biomechanics.
Table of Contents
Preface.- Part I. Theoretical and Experimental Aspects. Introduction. 1. Physical and Geometrical Background. 2.Crystalline Materials with Thermo. inelastic Memory. 3. Normality Rule? Plastic Work Extremals and Related Topics. 4. Thermodynamics of Inelasticity. 5. Some Multiaxial Viscoplastic Experiments. Relation to Tensor Functions.- Part II. Some General Problems. 6. Viscoplasticity of Ferromagnetics. 7. Self. Consistent Method and Quasi. Rate Dependent Polycrystals. 8. Inelastic Micromorphic Polycrystals. Conclusions related to Parts I and II.- Part III. Applications of the Theory. 9. Plastic Wave Propagation in Hopkinson Bar. 10. Ratchetting Phenomenon at Low Strain Rates for AISI 16H Stainless Steel. 11. Stress and Strain Measures for Othotropic Metals at Large Nonproportional Plastic Strain Histories. Remarks on the Application of the Theory.- References. Glossary. Index.