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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.

Service loading histories have the same general character for an individual route and the magnitudes vary from driver to driver. Both the magnitude and character of the loading history change from route to route and a linear scaling of one loading history does not characterize the variability of usage over a wide range of operating conditions. In this paper a technique for measuring and extrapolating cumulative exceedance diagrams to quantify the distribution of service loading in a vehicle is described. Monte Carlo simulations are coupled with the local stress strain approach for fatigue to obtain distributions of service loading. Fatigue life estimates based on the original loading histories are compared to those obtained from statistical descriptions of exceedance diagrams.

Methods for assessing the variability of fatigue lives of components subjected to variable amplitude loading are described. Monte Carlo simulations are coupled with the local stress strain approach to compute the distribution of fatigue lives that includes uncertainties in loading, material properties, geometry and fatigue damage.

Cyclic loading is not as damaging as static loading of ceramics at high temperatures. Microcrack growth retardation has been established as a mechanism for increasing the durability of ceramics at high temperatures. A combined experimental and theoretical approach provides a mechanistic understanding of the deformation and failure processes in ceramic materials at high temperatures. Results demonstrate that the high temperature behavior of some ceramic material systems are controlled by the behavior of the grain boundary phase whose response is considerably different under static and cyclic loading.

This paper traces the development of small field data acquisition and analysis systems. The impact of some significant recent advances in microelectronics on the design of field test systems is detailed. Techniques for the exploitation of newly developed microelectronic devices to design field test systems based on the concepts of distributed computing and modular hardware and software organization are discussed. The paper concludes with a description of a recently developed test system which embodies the newly available capabilities.

This paper reviews fatigue life estimation techniques. The methods are the result of many researchers and practicing engineers. No attempt is made to cite individual contributions. A bibilography of useful sources of information is included.