Requirements for microstructural investigations of steels used in modern power plants
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Christina Scheu
,
Gernot Zies
Abstract
The thermo-mechanical behaviour of newly developed 9 – 12 wt.% Cr steels used in steam power plants depends strongly on the microstructure. In the present work, a combination of various microscopy techniques is used to study the microstructural features relevant for the creep resistance. These include the subgrain size, the number of free dislocations, the chemical composition and crystallographic structure of the occurring precipitates, and their density and size distribution. Accordingly, the techniques which were applied range from light microscopy to transmission electron microscopy in order to cover all lengthscales from the millimeter regime to the nanometer level. These detailed investigations are important for alloy design and as input parameters for thermodynamical calculations and modelling of the microstructural evolution to develop steels for cleaner power stations with high thermal efficiency.
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This study was partially funded by the BMWT (Bundesministerium für Wirtschaft und Technologie) in the framework of COST 522. The authors gratefully acknowledge the support of the colleagues, and steel and steam plant manufacturers involved in the COST project. Many thanks to Dr. K. Spiradek-Hahn and Dr. J. Wosik, both from ARC Seibersdorf, for fruitful discussions about the test material. The authors wish to thank D. Willer for the SEM and R. Scheck for the LM investigations. The authors gratefully acknowledge the technical support of H. Strunk (TEM measurements) and G. Strohschein (image processing). Helpful discussions with Dr. H. Ruoff and D. Kuppler are acknowledged.
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© 2005 Carl Hanser Verlag, München
Articles in the same Issue
- Frontmatter
- Editorial
- Editorial
- Articles Basic
- Identifying creep mechanisms in plastic flow
- A unified microstructural metal plasticity model applied in testing, processing, and forming of aluminium alloys
- Implications of non-negligible microstructural variations during steady-state deformation
- Tertiary creep of metals and alloys
- Interactions between particles and low-angle dislocation boundaries during high-temperature deformation
- Strain-rate sensitivity of ultrafine-grained materials
- Transient plastic flow at nominally fixed structure due to load redistribution
- Vacancy concentrations determined from the diffuse background scattering of X-rays in plastically deformed copper
- Effect of heating rate in α + γ dual-phase field on lamellar microstructure and creep resistance of a TiAl alloy
- About stress reduction experiments during constant strain-rate deformation tests
- Finite-element modelling of anisotropic single-crystal superalloy creep deformation based on dislocation densities of individual slip systems
- Variational approach to subgrain formation
- Articles Applied
- Pseudoelastic cycling of ultra-fine-grained NiTi shape-memory wires
- Creep properties at 125 °C of an AM50 Mg alloy modified by Si additions
- Dependence of mechanical strength on grain structure in the γ′ and oxide dispersions-trengthened nickelbase superalloy PM 3030
- On the improvement of the ductility of molybdenum by spinel (MgAl2O4) particles
- Hot workability and extrusion modelling of magnesium alloys
- Characterization of hot-deformation behaviour of Zircaloy-2: a comparison between kinetic analysis and processing maps
- Requirements for microstructural investigations of steels used in modern power plants
- Influence of Lüders band formation on the cyclic creep behaviour of a low-carbon steel for piping applications
- Creep and creep rupture behaviour of 650 °C ferritic/martensitic super heat resistant steels
- Toughening mechanisms of a Ti-based nanostructured composite containing ductile dendrites
- Notifications/Mitteilungen
- Personal/Personelles
- News/Aktuelles
- Conferences/Konferenzen
Articles in the same Issue
- Frontmatter
- Editorial
- Editorial
- Articles Basic
- Identifying creep mechanisms in plastic flow
- A unified microstructural metal plasticity model applied in testing, processing, and forming of aluminium alloys
- Implications of non-negligible microstructural variations during steady-state deformation
- Tertiary creep of metals and alloys
- Interactions between particles and low-angle dislocation boundaries during high-temperature deformation
- Strain-rate sensitivity of ultrafine-grained materials
- Transient plastic flow at nominally fixed structure due to load redistribution
- Vacancy concentrations determined from the diffuse background scattering of X-rays in plastically deformed copper
- Effect of heating rate in α + γ dual-phase field on lamellar microstructure and creep resistance of a TiAl alloy
- About stress reduction experiments during constant strain-rate deformation tests
- Finite-element modelling of anisotropic single-crystal superalloy creep deformation based on dislocation densities of individual slip systems
- Variational approach to subgrain formation
- Articles Applied
- Pseudoelastic cycling of ultra-fine-grained NiTi shape-memory wires
- Creep properties at 125 °C of an AM50 Mg alloy modified by Si additions
- Dependence of mechanical strength on grain structure in the γ′ and oxide dispersions-trengthened nickelbase superalloy PM 3030
- On the improvement of the ductility of molybdenum by spinel (MgAl2O4) particles
- Hot workability and extrusion modelling of magnesium alloys
- Characterization of hot-deformation behaviour of Zircaloy-2: a comparison between kinetic analysis and processing maps
- Requirements for microstructural investigations of steels used in modern power plants
- Influence of Lüders band formation on the cyclic creep behaviour of a low-carbon steel for piping applications
- Creep and creep rupture behaviour of 650 °C ferritic/martensitic super heat resistant steels
- Toughening mechanisms of a Ti-based nanostructured composite containing ductile dendrites
- Notifications/Mitteilungen
- Personal/Personelles
- News/Aktuelles
- Conferences/Konferenzen
