High Temperature Creep Fatigue

A compendium of European and worldwide research investigating creep, fatigue and failure behaviors in metals under high-temperature and other service stresses. It helps set the standards for coordinating creep data and for maintaining defect-free quality in high-temperature metals and metal-based weldments.

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.

A compilation of data collected and maintained for many years as the property of a large aluminum company, which decided in 1997 to make it available to other engineers and materials specialists. In tabular form, presents data on the tensile and creep properties of eight species of wrought alloys and five species of cast alloys in the various shapes used in applications. Then looks at the fatigue data for several alloys under a range of conditions and loads. The data represent the typical or average findings, and though some were developed years ago, the collection is the largest and most detailed available. There is no index.

The global energy consumption is increasing and together with global warming from greenhouse gas emission, create the need for more environmental friendly energy production processes. Higher efficiency of biomass power plants can be achieved by increasing temperature and pressure in the boiler section and this would increase the generation of electricity along with the reduction in emission of greenhouse gases e.g. CO2. The power generation must also be flexible to be able to follow the demands of the energy market, this results in a need for cyclic operating conditions with alternating output and multiple start-ups and shut-downs. Because of the demands of flexibility, higher temperature and higher pressure in the boiler section of future biomass power plants, the demands on improved mechanical properties of the materials of these components are also increased. Properties like creep strength, thermomechanical fatigue resistance and high temperature corrosion resistance are critical for materials used in the next generation biomass power plants. Austenitic stainless steels are known to possess such good high temperature properties and are relatively cheap compared to the nickel-base alloys, which are already operating at high temperature cyclic conditions in other applications. The behaviour of austenitic stainless steels during these widened operating conditions are not yet fully understood. The aim of this licentiate thesis is to increase the knowledge of the mechanical behaviour at high temperature cyclic conditions for austenitic stainless steels. This is done by the use of thermomechanical fatigue- and creepfatigue testing at elevated temperatures. For safety reasons, the effect of prolonged service degradation is investigated by pre-ageing before mechanical testing. Microscopy is used to investigate the microstructural development and resulting damage behaviour of the austenitic stainless steels after testing. The results show that creep-fatigue interaction damage, creep damage and oxidation assisted cracking are present at high temperature cyclic conditions. In addition, simulated service degradation resulted in a detrimental embrittling effect due to the deterioration by the microstructural evolution.

Provides information from around the world on creep in multiple high-temperature metals, alloys, and advanced materials.