Low Cycle Fatigue And Life Prediction

This text describes the mathematical formulation and proof of the unified mechanics theory (UMT) which is based on the unification of Newton’s laws and the laws of thermodynamics. It also presents formulations and experimental verifications of the theory for thermal, mechanical, electrical, corrosion, chemical and fatigue loads, and it discusses why the original universal laws of motion proposed by Isaac Newton in 1687 are incomplete. The author provides concrete examples, such as how Newton’s second law, F = ma, gives the initial acceleration of a soccer ball kicked by a player, but does not tell us how and when the ball would come to a stop. Over the course of Introduction to Unified Mechanics Theory, Dr. Basaran illustrates that Newtonian mechanics does not account for the thermodynamic changes happening in a system over its usable lifetime. And in this context, this book explains how to design a system to perform its intended functions safely over its usable life time and predicts the expected lifetime of the system without using empirical models, a process currently done using Newtonian mechanics and empirical degradation/failure/fatigue models which are curve-fit to test data. Written as a textbook suitable for upper-level undergraduate mechanics courses, as well as first year graduate level courses, this book is the result of over 25 years of scientific activity with the contribution of dozens of scientists from around the world including USA, Russia, Ukraine, Belarus, Spain, China, India and U.K.

This book represents the final reports of the scientific projects funded within the DFG-SPP1466 and, hence, provides the reader with the possibility to familiarize with the leading edge of VHCF research. It draws a balance on the existing knowledge and its enhancement by the joint research action of the priority program. Three different material classes are dealt with: structural metallic materials, long-fiber-reinforced polymers and materials used in micro-electro-mechanical systems. The project topics address the development of suitable experimental techniques for high-frequency testing and damage monitoring, the characterization of damage mechanisms and damage evolution, the development of mechanism-based models and the transfer of the obtained knowledge and understanding into engineering regulations and applications.

This book gives an introduction to computational plasticity and includes the kinematics of large deformations, together with relevant continuum mechanics. Central to the book is its focus on computational plasticity, and we cover an introduction to the finite element method which includes both quasi-static and dynamic problems. We then go on to describe explicit and implicit implementations of plasticity models in to finite element software. Throughout the book, we describe thegeneral, multiaxial form of the theory but uniquely, wherever possible, reduce the equations to their simplest, uniaxial form to develop understanding of the general theory and, we hope, physical insight. We provide several examples of implicit and explicit implementations of von Mises time-independentand visco-plasticity in to the commercial code ABAQUS (including the fortran coding), which should prove invaluable to research students and practising engineers developing ABAQUS 'UMATs'. The book bridges the gap between undergraduate material on plasticity and existing advanced texts on nonlinear computational mechanics, which makes it ideal for students and practising engineers alike. It introduces a range of engineering applications, including superplasticity, porous plasticity, cyclicplasticity and thermo-mechanical fatigue, to emphasize the subject's relevance and importance.

In 1979 the first InternationalSymposium on Low CycleFatigue and Elasto-Plastic Behaviour of Materials was held in Stuttgart, FRG. Since then research in low cycle fatigue has proceeded rapidly. The vital interest of engineers and researchers in communicating the rapid advances in the ongoing research in low cycle fatigue has encouraged me to initiate again the Second International Conference which was held in Munich, FRG, 7-11 September 1987. Failure in low cycle fatigue represents a serious problem in the design and opera tion of highly stressed structures. Under complex loading and environmental cir cumstances, especially for high temperature services, reliable life prediction can not be expected without detailed consideration of the failure mechanism and with out extensive use of mechanistic approaches. The purpose of this conference was to provide a forum to discuss the advances in recent research in the field of low cycle fatigue. The conference was intended to help to further bridge the gap between those who are involved in basic research, and the engineers who have to perform the design of highly stressed structural components.

This book provides practicing engineers, researchers, and students with a working knowledge of the fatigue design process and models under multiaxial states of stress and strain. Readers are introduced to the important considerations of multiaxial fatigue that differentiate it from uniaxial fatigue.