Metal Plasticity And Fatigue At High Temperature

In several industrial fields (such as automotive, steelmaking, aerospace, and fire protection systems) metals need to withstand a combination of cyclic loadings and high temperatures. In this condition, they usually exhibit an amount—more or less pronounced—of plastic deformation, often accompanied by creep or stress-relaxation phenomena. Plastic deformation under the action of cyclic loadings may cause fatigue cracks to appear, eventually leading to failures after a few cycles. In estimating the material strength under such loading conditions, the high-temperature material behavior needs to be considered against cyclic loading and creep, the experimental strength to isothermal/non-isothermal cyclic loadings and, not least of all, the choice and experimental calibration of numerical material models and the selection of the most comprehensive design approach. This book is a series of recent scientific contributions addressing several topics in the field of experimental characterization and physical-based modeling of material behavior and design methods against high-temperature loadings, with emphasis on the correlation between microstructure and strength. Several material types are considered, from stainless steel, aluminum alloys, Ni-based superalloys, spheroidal graphite iron, and copper alloys. The quality of scientific contributions in this book can assist scholars and scientists with their research in the field of metal plasticity, creep, and low-cycle fatigue.

In several industrial fields (such as automotive, steelmaking, aerospace, and fire protection systems) metals need to withstand a combination of cyclic loadings and high temperatures. In this condition, they usually exhibit an amount--more or less pronounced--of plastic deformation, often accompanied by creep or stress-relaxation phenomena. Plastic deformation under the action of cyclic loadings may cause fatigue cracks to appear, eventually leading to failures after a few cycles. In estimating the material strength under such loading conditions, the high-temperature material behavior needs to be considered against cyclic loading and creep, the experimental strength to isothermal/non-isothermal cyclic loadings and, not least of all, the choice and experimental calibration of numerical material models and the selection of the most comprehensive design approach. This book is a series of recent scientific contributions addressing several topics in the field of experimental characterization and physical-based modeling of material behavior and design methods against high-temperature loadings, with emphasis on the correlation between microstructure and strength. Several material types are considered, from stainless steel, aluminum alloys, Ni-based superalloys, spheroidal graphite iron, and copper alloys. The quality of scientific contributions in this book can assist scholars and scientists with their research in the field of metal plasticity, creep, and low-cycle fatigue.

From concept to application, this book describes the method of strain-range partitioning for analyzing time-dependent fatigue. Creep (time-dependent) deformation is first introduced for monotonic and cyclic loading. Multiple chapters then discuss strain-range partitioning in details for multi-axial loading conditions and how different loading permutations can lead to different micro-mechanistic effects. Notably, the total-strain method of strain-range partitioning (SRP) is described, which is a methodology that sees use in several industries. Examples from aerospace illustrate applications, and methods for predicting time-dependent metal fatigue are critiqued.

Hardbound. Low cycle fatigue failures have been identified as being connected with the low number of repeated working cycles of equipment which usually results from start-up, shut-down operations, or some necessary interruption of ordinary use. The vast amount of research carried out so far has shown that only detailed knowledge of the proper mechanisms, and thus recognition of the important parameters governing the fatigue failure, can effectively improve engineering design procedures. This book concentrates on the physical metallurgy approach to elastoplastic cyclic straining and its relation to the fatigue life of metals. Recent breakthroughs in the understanding of the appropriate mechanisms is summarized and the importance of short crack growth is emphasised. Special attention is given to the identification of the basic mechanisms underlying cyclic plastic straining, damage evolution, fatigue crack initiation and growth, which results in final frac

About 35 years ago, thermal fatigue was identified as an important phenomenon which limited the lifetime of high temperature plant. In the intervening years many investigations have been carried out, primarily to give guidance on likely endurance (especially in the presence of time dependent deformation) but latterly, with the introduction of sophisticated testing machines, to provide knowledge of the underlying mechanisms of failure. A previous edited book (Fatigue at High Temperature, Elsevier Applied Science Publishers, 1983) summarised the state-of-the-art of high temperature fatigue testing and examined the factors influencing life, such as stress state, environment and microstructural effects. It also considered, in some detail, cyclic crack growth as a more rigorous approach to life limitation. The aim of the present volume (which in style and format follows exactly the same lines as its predecessor) is once again to pursue the desire to translate detailed laboratory knowledge into engineering design and assessment. There is, for example, a need to consider the limitations of the laboratory specimen and its relationship with engineering features. Many design procedures still rely on a simple endurance approach based on failure of a smooth specimen, and this is taken to indicate crack initiation in the component. In this volume, therefore, crack propagation is covered only incidentally, emphasis being placed instead on basic cyclic stress strain properties, non-isothermal behaviour, metallography, failure criteria and the need for agreed testing procedures.