Recent advances in creep-resistant steels for power plant applications

Ennis, P. J.; Czyrska‐Filemonowicz, A.

doi:10.1007/bf02706455

Cited by 274 publications

(196 citation statements)

References 5 publications

Supporting

Mentioning

184

Contrasting

Order By: Relevance

“…Detailed particle analysis on the carbon extraction replicas from this sample shows that the undissolved precipitates after the simulated weld thermal cycle are mainly of the MX type, with the M 23 C 6 carbides having been almost completely dissolved (Table IV). This is consistent with observations in the literature for Grade 92 steel that the M 23 C 6 carbides are not stable at temperatures over 1273 K (1000°C), [5] and indeed the predicted dissolution temperature of M 23 C 6 carbides in Grade 92 steel is 1163 K (890°C) according to thermodynamic equilibrium calculations. [27] It was possible to compare the ion-beam-induced secondary electron micrographs with EBSD analysis of identical regions (Figure 12), which has shown that these undissolved particles are not closely associated with PAGBs or substructure boundaries.…”

Section: Discussionsupporting

confidence: 91%

“…[5,30] It is worth noting that the conventional definitions of the HAZ microstructure, primarily in low alloy steel welds, involves a further classification of the regions with a peak temperature above the Ac 3 temperature into the so-called coarse-grain and fine-grain regions, related to whether the grain structure was significantly influenced by second-phase particles. [1,2,14] However, it was observed in this case that the rapid weld thermal cycle results in the Ac 3 temperature being close to the temperature at which the pre-existing secondary precipitates are completely dissolved.…”

Section: Discussionmentioning

confidence: 99%

“…It is a tempered martensitic steel with a nominal chemical composition of 9Cr-0.5Mo-1.8WVNb (wt pct), which is typically heat treated by normalization at 1313 K to 1353 K (1040°C to 1080°C) followed by tempering at 1023 K to 1053 K (750°C to 780°C) [4] to achieve a tempered martensitic microstructure in combination with the secondary precipitates such as the grain boundary M 23 C 6 carbides and the MX carbonitrides. [5] A variety of conventional arc welding techniques, such as gas tungsten arc welding (GTAW), shielded metal arc welding (SMAW), and submerged arc welding, [6] are routinely applied in the fabrication of Grade 92 steel components.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The Influence of Thermal Cycles on the Microstructure of Grade 92 Steel

West

Siefert³

et al. 2017

Metall Mater Trans A

View full text Add to dashboard Cite

The microstructure in the heat-affected zone (HAZ) of welds made from the 9 wt pct chromium martensitic Grade 92 steel is complex and has not yet been completely understood. There is a lack of systematic microstructural investigations to define the different regions of the microstructure across the HAZ of Grade 92 steel welds as a function of the welding process. In this study, the microstructure in the HAZ of an as-fabricated single-pass bead-on-plate weld on a parent metal of Grade 92 steel was systematically investigated by using an extensive range of electron and ion-microscopy-based techniques. A dilatometer was used to apply controlled thermal cycles to simulate the microstructures in the different regions of the HAZ. A wide range of microstructural properties in the simulated materials were then characterized and compared with the experimental observations from the weld HAZ. It was found that the microstructure in the HAZ of a single-pass Grade 92 steel weld can be categorized as a function of a decreasing peak temperature reached as (1) the completely transformed (CT) region, in which the original matrix is completely reaustenitized with complete dissolution of the pre-existing secondary precipitate particles; (2) the partially transformed (PT) region, where the original matrix is partially reaustenitized along with a partial dissolution of the secondary precipitate particles from the original matrix; and (3) the overtempered (OT) region, where the pre-existing precipitate particles coarsen. The PT region is considered to be the susceptible area for damage in the commonly reported HAZ failures in weldments constructed from these types of steels.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The Influence of Thermal Cycles on the Microstructure of Grade 92 Steel

West

Siefert³

et al. 2017

Metall Mater Trans A

View full text Add to dashboard Cite

show abstract

“…see [15,54]. To identify an initial value within this range for the P91 steel presented here, the cyclic softening material parameter α 1 and the initial dislocation density, ρ 0 , are identified from the measured initial yield stress across the range of temperatures by rearranging equation (4).…”

Section: Parameter Identificationmentioning

confidence: 99%

A dislocation-based model for high temperature cyclic viscoplasticity of 9–12Cr steels

Barrett

O’Donoghue

Leen

2014

Computational Materials Science

View full text Add to dashboard Cite

“…In this way, a reduction of the fuel consumption can be achieved as well as of pollutant gases emissions [1]. To achieve that goal, the use of more expensive materials which are able to resist ultra-supercritical conditions (USC) at 625-650°C is demanded [2]. The new generation of 9-10% Cr steels owns enough mechanical properties [3] to be considered as candidate to manufacture turbine components, but they exhibit a limited oxidation resistance at USC in steam atmosphere [4].…”

Section: Introductionmentioning

confidence: 99%