1st Edition

Introduction to Thermodynamics of Mechanical Fatigue

By Michael M. Khonsari, Mehdi Amiri Copyright 2013
    166 Pages 94 B/W Illustrations
    by CRC Press

    166 Pages 94 B/W Illustrations
    by CRC Press

    Fatigue is probabilistic in nature and involves a complex spectrum of loading history with variable amplitudes and frequencies. Yet most available fatigue failure prediction methods are empirical and concentrate on very specific types of loading. Taking a different approach, Introduction to Thermodynamics of Mechanical Fatigue examines the treatment of fatigue via the principles of thermodynamics. It starts from the premise that fatigue is a dissipative process and must obey the laws of thermodynamics. In general, it can be hypothesized that mechanical degradation is a consequence of irreversible thermodynamic processes. This suggests that entropy generation offers a natural measure of degradation.

    An Entropic Approach to Fatigue and Degradation

    Drawing on recent cutting-edge research and development, the authors present a unified entropic approach to problems involving fatigue. They introduce the fundamentals of fatigue processes and explore a wide range of practical engineering applications.

    Fundamental Concepts and Methodologies

    The book reviews commonly observed failure modes, discusses how to analyze fatigue problems, and examines the deformation characteristics of a solid material subjected to fatigue loading. It also looks at how to use thermodynamics to determine the onset of fatigue failure. In addition, the book presents methodologies for improving fatigue life and for accelerated fatigue testing.

    Learn How to Apply the Entropic Approach to Fatigue Problems

    Comprehensive and well organized, this work helps readers apply powerful thermodynamics concepts to effectively treat fatigue problems at the design stage. It offers an accessible introduction to a new and exciting area of research in the field of fatigue failure analysis.

    Introduction to Mechanical Degradation Processes
    Brinelling and False Brinelling
    Thermal Shock

    Fundamentals of Thermodynamics
    Open and Closed Systems
    Equilibrium and Nonequilibrium State
    Steady and Unsteady State
    Stable and Unstable State
    The First Law of Thermodynamics
    The Second Law of Thermodynamics
    Entropy Flow and Entropy Generation
    Entropy Balance Equation

    Degradation-Entropy Generation (DEG) Theorem
    Thermodynamic Forces and Flows
    Relations between Thermodynamic Forces and Flows
    The Degradation–Entropy Generation Theorem

    Fatigue Mechanisms: An Overview
    Multiscale Characteristics of Fatigue
    Parameters Influencing Fatigue and Classification of Regimes
    Fatigue and Energy Dissipation
    Fatigue-Temperature Rise

    Basic Thermodynamic Framework for Fatigue Analysis
    Entropy Balance Equation of a Deformed Body
    Entropy Change of a Thermally Deformed Solid
    Clausius–Duhem Inequality
    Thermodynamic Forces and Flows in Fatigue

    Thermodynamic Assessment of Fatigue Failure
    Limitation of Conventional Methods and the Need for Further Advances
    Evaluation of Entropy Generation and Entropy Flow
    Time to Failure

    Damage Mechanics: An Entropic Approach
    Introduction to Damage Mechanics
    Continuum Damage Mechanics (CDM)

    Self-Organization in Fatigue
    Introduction to Self-Organization
    Effect of Electric Current on Fatigue Life
    Effect of Magnetic Field on Fatigue Life
    Effect of Environment (Surface Cooling) on Fatigue Life
    Self-Organization and Complexity

    Entropic Fatigue: In Search for Applications
    Application to Variable-Loading Amplitude and Structural Health Monitoring
    Accelerated Fatigue Testing
    Concluding Remarks



    Michael Khonsari is the holder of the Dow Chemical Endowed Chair and Professor of the Mechanical Engineering Department at Louisiana State University where he directs the Center for Rotating Machinery (CeRoM). Professor Khonsari is a fellow of ASME, STLE, and the American Association for the Advancement of Science (AAAS). He holds several patents and he has authored two books and over 240 archival journal articles, book chapters, and special publications. He is currently the chief editor of the ASME Journal of Tribology.

    Mehdi Amiri earned his Ph.D. in mechanical engineering from Louisiana State University where he is currently a research associate in the Center for Rotating Machinery (CeRoM). His area of research is in the field of fatigue and fracture analysis. He holds one patent and has authored several journal publications. His research interests include thermal/fluid mechanics, thermodynamics, tribology, and failure analysis.