Long-term microstructural stability and mechanical properties of 9Cr3W3Co heat-resistant steel for ultra-supercritical units
Source abstract
Abstract
9Cr3W3Co heat-resistant steel has become a widely used material for key components in advanced ultra-supercritical thermal power units due to its excellent high-temperature properties and corrosion resistance. In this study, the steel was subjected to aging treatment at different temperatures and times, then the microstructure and mechanical properties were investigated. After long-term aging, Laves phase forms along martensite lath boundaries and prior austenite boundaries. With increasing aging time and temperature, the width of martensite lath and the size of M 23 C 6 carbides increase. The Laves phase particles grow from 0.210 μm to 0.351 μm, and their morphology changes from regular short-rod shapes to irregular ones. The coarsening rate of Laves phase reaches a maximum at 630°C. Moreover, hardness exhibits a slight decrease with increasing aging temperature and time. Plasticity, strength, and the growth and aggregation of precipitates all influence the impact properties. After 20,000 h of aging, both yield strength and elongation remain at relatively high levels, with impact energy values all exceeding 20 J. After 30,000 h of aging, the coarsening of precipitates has a more pronounced effect on impact toughness. In summary, 9Cr3W3Co heat-resistant steel maintains high stabilities of microstructure and property after long-term exposure at high temperature.
Source: openalex_inverted_index · Quality: baseline
Research context
OpenAlex topics: High Temperature Alloys and Creep · Microstructure and Mechanical Properties of Steels · Heat transfer and supercritical fluids
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (40)
Show source-provided references
1. Exergoenvironmental analysis of a ultra-supercritical coal-fired power plant10.1016/j.jclepro.2019.05.214 ↗
2. Clean coal conversion processes – progress and challenges10.1039/b809218b ↗
3. Ultra supercritical thermal power plant material advancements: a review
4. Failure analysis of a martensitic stainless steel steam turbine blade10.1007/s40430-024-04952-5 ↗
5. Research on the low carbon development path of China's coal industry under carbon peaking & carbon neutral target: based on the RCPs-SSPs framework10.1016/j.resourpol.2023.104091 ↗
6. Practical limitations in improving power generation efficiency: challenges of boiler materials and the response of heat resistant steel10.1016/j.rser.2025.115973 ↗
7. The influence of long-term thermal exposure on microstructural stabilization and mechanical properties in 9Cr-0.5Mo-1.8 W-VNb heat-resistant steel10.1016/j.msea.2016.07.006 ↗
8. Microstructural evolution of delta ferrite in SAVE12 steel under heat treatment and short-term creep10.1016/j.matchar.2012.08.009 ↗
9. Fracture characteristics of thermally exposed 9Cr–1Mo steel after tensile and impact testing at room temperature10.1016/j.engfailanal.2008.09.003 ↗
10. Microstructure and properties of G115 steel aged at 650°C
11. Effect of boron on G115 martensitic heat resistant steel during aging at 650°C10.1016/j.msea.2020.139529 ↗
12. Nano-sized MX carbonitrides contribute to the stability of mechanical properties of martensite ferritic steel in the later stages of long-term aging10.1016/j.actamat.2019.06.012 ↗
13. Evolution of strengthening factors during long-term aging at 650°C in advanced 10% Cr heat-resistant steel10.1088/1757-899X/1014/1/012010 ↗
14. Effect of microstructural evolution on high-temperature strength of 9Cr–3W–3Co martensitic heat resistant steel under different aging conditions10.1016/j.msea.2013.09.033 ↗
15. Characterization and numerical simulation of nucleation–growth–coarsening kinetics of precipitates in G115 martensitic heat resistance steel during long-term aging10.1007/s42243-022-00854-9 ↗
16. Study on the effect of ageing on laves phase evolution and their effect on mechanical properties of P92 steel10.1016/j.msea.2018.01.035 ↗
17. Effect of long-term aging at 630°Con microstructure and mechanical properties of FB2 rotor steel
18. Effect of boron element on the microstructural evolution and properties of a novel 9Cr martensitic heat-resistant steel during long-term aging at 630°C10.1016/j.jmrt.2025.04.026 ↗
19. Theoretical investigation of stabilizing mechanism by boron in body-centered cubic iron through (Fe,Cr)23(C,B)6 precipitates10.1007/s11661-016-3397-7 ↗
20. Evolutions on microstructure and impact toughness of G115 steel after long-term aging at 700°C10.3390/met14080921 ↗
21. Toughness evolution of 9Cr–3W–3Co martensitic heat resistant steel during long time aging10.1016/j.msea.2015.09.115 ↗
22. Some studies on P91 steel and their weldments10.1016/j.jallcom.2018.01.120 ↗
23. Stability study of COST-FB2 Steel for ultra-supercritical unit rotors during long-term aging at 630°C
24. Effect of long-term aging on the microstructure evolution and fracture mechanism of 9% Cr steels10.1016/j.msea.2024.146133 ↗
25. Microstructural evolution and its effect on tensile properties of 10Cr-2W-3Co martensitic steel during thermal exposure
26. Mo-rich laves phase in a 9.5Cr-1.5MoCoVNbNB heat-resistant steel during long-term aging at 620°C10.1016/j.matchar.2021.111588 ↗
27. Effect of long-term thermal aging on microstructure evolution and creep deformation behavior of a novel 11Cr-3W-3Co martensite ferritic steel10.3390/ma15103659 ↗
28. Importance of cold rolling and tempering on the microstructure evolution, precipitation behavior and mechanical responses of 9Cr3Co3W1Cu ferritic/martensitic steel
29. On laves phase in a 9Cr3W3CoB martensitic heat resistant steel when aged at high temperatures10.1016/j.jmst.2020.12.062 ↗
30. The effect of microstructure evolution on the mechanical properties of martensite ferritic steel during long-term aging10.1016/j.actamat.2017.03.045 ↗
31. Influence of precipitated phases on properties during prolonged aging in TP347H steel at 700°C10.1080/09603409.2017.1279511 ↗
32. Effect of long-term aging at 620 °C on microstructure and properties of COST-FB2 steel for steam turbine rotors
33. Nucleation of W-rich carbides and laves phase in a Re-containing 10% Cr steel during creep at 650°C10.1016/j.matchar.2020.110651 ↗
34. Microstructural evolution and its influence on the impact toughness of GH984G alloy during long-term thermal exposure10.1016/j.jmst.2020.06.005 ↗
35. Impact toughness of a modified HR3C austenitic steel after long-term thermal exposure at 650°C10.1016/j.msea.2018.10.084 ↗
36. Effect of aging on the impact toughness of 25Cr–20Ni–Nb–N steel10.1016/j.msea.2009.12.039 ↗
37. Effect of hot-rolling on the microstructure and impact toughness of an advanced 9%Cr steel10.3390/cryst13030492 ↗
38. Effect of grain boundary evolution on the microstructure and cryogenic impact toughness of high alloy austenitic stainless steel
39. Study on the microstructure evolution and effect on mechanical properties of P92 steel during long term service10.1016/j.mtla.2024.102124 ↗
40. Microstructure and long-term creep properties of 9–12% Cr steels10.1016/j.ijpvp.2007.06.010 ↗