Multiaxial Fatigue And Fracture

This volume contains 18 papers selected from 90 presented at the Fifth International Conference on Biaxial/Multiaxial Fatigue and Fracture held in Cracow, Poland 8-12 September 1997. The papers in this book deal with theoretical, computational and experimental aspects of the multiaxial fatigue and fracture of engineering materials and structures. The papers are divided into the following four categories: 1. Proportional cyclic loading 2. Non-proportional cyclic loading 3. Variable amplitude and random loading 4. Crack growth Most papers in this publication talk about the behaviour of constructional materials and elements of machines under non-proportional loading and under variable amplitude and random loading, which are more realistic load histories met in industrial practice. Variable amplitude loading under cyclic load with basic frequency and random loading under load with a continuous band of frequency is classified here. This book gives a review of the latest world success and directions of investigations on multiaxial fatigue and fracture. More and more often publications are results of the co-operation of researchers from different laboratories and countries. Seven out of eighteen papers included here were worked out by international authors teams. This is a symptom of the times, when science and investigations know no borders.

The European Structural Integrity Society (ESIS) Technical Commitee on Fatigue of Engineering Materials and Structures (TC3) decided to compile a Special Technical Publication (ESIS STP) based on the 115 papers presented at the 6th International Conference on Biaxial/Multiaxial Fatigue and Fracture. The 25 papers included in the STP have been extended and revised by the authors. The conference was held in Lisbon, Portugal, on 25-28 June 2001, and was chaired by Manual De Freitas, Instituto Superior Tecnico, Lisbon. The meeting, organised by the Instituto Superior Tecnico and sponsored by the Portuguese Minesterio da Cienca e da Tecnologia and by the European Structural Integrity Society, was attended by 151 delegates from 20 countries. The papers in the present book deal with the theoretical, numerical and experimental aspects of the Multiaxial fatigue and fracture of engineering materials and structures. They are divided in to the following six sections; Multiaxial Fatigue of Welded Structures; High cycle Multiaxial fatigue; Non proportional and Variable-Amplitude loading; Defects, Notches, Crack Growth; Low Cycle Multiaxial Fatigue; Applications and Testing Methods. As is well-known, most engineering components and structures in the mechanical, aerospace, power generation, and other industries are subjected to multiaxial loading during their service life. One of the most difficult tasks in design against fatigue and fracture is to translate the information gathered from uniaxial fatigue and fracture tests on engineering materials into applications involving complex states of cyclic stress-strain conditions. This book is the result of co-operation between many researchers from different laboratories, universities and industries in a number of countries.

Papers presented at the ASTM Symposium on Multiaxial Fatigue, held in San Diego, November 1991, to communicate the most recent international advances in multiaxial cyclic deformation and fatigue research as well as applications to component analysis and design. The 24 papers are grouped into five ca

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.

Problems often arise when attempting to determine the fatigue behaviour of structural components from laboratory data. A major reason for this lack of correlation is that most engineering components operate in stress environments significantly more complicated than uniaxial tension, the stress state in which most research studies are conducted. A review of the literature has shown that virtually all fatigue and fracture properties of metals and components are affected by multidirectional loading. In particular, variations in stress state compared with uniaxial tension produce the following effects: a) decreases in the fatigue limit by up to approximately 50%; b) increases or decreases in low-cycle fatigue life by factors of up to 20, depending on whether the stress in the second direction is tensile or compressive and is static or cyclic; c) out-of-phase loading also reduces the low-cycle fatigue life by a factor of up to 4 compared with in-phase loading; and d) acceleration and retardations of fatigue crack growth rates by factors of 3 to 4 depending on the nature of the transverse stress. It is also evident that multiaxial criteria used for design purposes can be non-conservative, especially under out-of-phase loading, and consequently can lead to unsafe estimates of the fatigue life of a component. Originator supplied keywords include: Multiaxial stress; Low cycle fatigue; Fracture properties; Fatigue tests; Crack propagation; Metal fatigue.

Fourteen papers from the May 1995 symposium focus on the advances that new materials testing equipment and digital computers have made possible. Representative topics: testing facilities for multiaxial loading of tubular specimens, biaxial deformation experiments over multiple string regimes, charac

Contains papers from a May 1999 symposium, describing state-of-the-art multiaxial testing techniques and analytical methods for characterizing fatigue and deformation behaviors of engineering materials. Papers are classified into sections on multiaxial strength of materials, multiaxial deformation,