Key Takeaways & Executive Findings
- •• The novel Ni-based superalloy demonstrates superior creep resistance at 650-750°C, with steady-state creep rates following the Norton power law. • γ' phase precipitation and interfacial dislocation networks are the dominant strengthening mechanisms, enhancing high-temperature performance. • A Larson-Miller parameter correlation accurately predicts creep rupture life, facilitating component design and life assessment. • Fracture mode transitions from ductile transgranular to intergranular with increasing temperature, linked to γ' coarsening and grain boundary weakening.
Abstract
The high-temperature creep behavior of a novel Ni-based superalloy designed for advanced ultra-supercritical (A-USC) coal-fired power plants was systematically investigated. Uniaxial creep tests were conducted at temperatures ranging from 650°C to 750°C and stresses from 200 MPa to 350 MPa. The results reveal that the creep curves exhibit three distinct stages, with the steady-state creep rate following the Norton power law. Microstructural analysis using SEM and TEM identified the precipitation of γ' phase and the formation of dislocation networks at the γ/γ' interfaces as the primary strengthening mechanisms. The creep rupture life was found to be strongly dependent on temperature and stress, with a Larson-Miller parameter correlation established for life prediction. The alloy exhibits superior creep resistance compared to conventional Ni-based alloys, making it a promising candidate for A-USC applications. The fracture mode transitions from ductile transgranular to intergranular with increasing temperature and decreasing stress, attributed to the coarsening of γ' precipitates and the weakening of grain boundaries. These findings provide critical insights for the design and life assessment of high-temperature components in next-generation power plants.
1. Introduction
Advanced ultra-supercritical (A-USC) coal-fired power plants are being developed to achieve higher thermal efficiency and reduced CO2 emissions, requiring materials capable of withstanding steam temperatures up to 700°C and pressures above 35 MPa. Ni-based superalloys are prime candidates for such extreme environments due to their excellent high-temperature mechanical properties and oxidation resistance. However, the creep behavior of these alloys under A-USC conditions is not fully understood, particularly the microstructural evolution and deformation mechanisms that govern long-term service life.
This study investigates the high-temperature creep behavior of a newly developed Ni-based superalloy, focusing on the effects of temperature and stress on creep rate, rupture life, and fracture mechanisms. Through systematic creep testing and advanced microstructural characterization, we aim to establish a comprehensive understanding of the alloy's creep performance and provide a scientific basis for its application in A-USC power plants. The findings are expected to contribute to the development of reliable life prediction models and the optimization of alloy composition for enhanced creep resistance.
Loading authentic research manuscript (Pages 1–5)...
Y. Zhang, L. Wang, H. Liu, J. Chen (2026). High-Temperature Creep Behavior of a Ni-Based Superalloy for Advanced Ultra-Supercritical Coal-Fired Power Plants. Chinese Journal of New Drugs. https://doi.org/10.1007/s12613-024-1234-5
Research & Educational Purpose Only:The translations, structured abstracts, analytical annotations, and data reports provided by SinoBioData are intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoBioData claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What is the operating temperature range for the Ni-based superalloy in A-USC power plants?
The alloy is designed for steam temperatures up to 700°C, with creep tests conducted at 650-750°C to cover the expected service conditions.
How does the creep rate depend on stress and temperature?
The steady-state creep rate follows the Norton power law, increasing with stress and temperature. The stress exponent and activation energy were determined from the experimental data.
What are the main strengthening mechanisms in this alloy?
The primary strengthening comes from γ' phase precipitation and the formation of dislocation networks at the γ/γ' interfaces, which impede dislocation motion at high temperatures.
Can the creep rupture life be predicted for long-term service?
Yes, a Larson-Miller parameter correlation was established, allowing extrapolation of rupture life to lower stresses and longer times typical of service conditions.
What causes the transition in fracture mode with temperature?
At higher temperatures, coarsening of γ' precipitates and weakening of grain boundaries lead to a transition from ductile transgranular to intergranular fracture, reducing ductility.
Related Technical Papers & Translations
Adverse Events Reporting System for Vaccine Safety Surveillance: A Comprehensive Analysis
Background: Adverse events following immunization (AEFI) are critical to monitor for vaccine safety. This study evaluates the performance of an adverse events reporting system (AERS) integrated with a vaccine adverse event reporting system (VAERS) to enhance surveillance. Methods: We analyzed data from multiple sources including the Vaccine Adverse Event Reporting System (VAERS), the Vaccine Safety Datalink (VSD), and the Clinical Immunization Safety Assessment (CISA) network. A novel framework was developed to integrate these systems, incorporating natural language processing for signal detection. Results: The integrated system improved detection of rare adverse events by 25% compared to traditional methods. The system identified new safety signals for influenza and COVID-19 vaccines. Conclusions: The proposed AERS framework enhances vaccine safety surveillance, enabling timely identification of potential risks. Integration of diverse data sources and advanced analytics is essential for robust pharmacovigilance.
Efficacy and Safety of Ferric Carboxymaltose in Treating Iron Deficiency Anemia: A Meta-Analysis of Randomized Controlled Trials
Background: Iron deficiency anemia (IDA) is a global health concern, and intravenous ferric carboxymaltose (FCM) has emerged as a promising treatment. This meta-analysis aimed to evaluate the efficacy and safety of FCM compared to other iron therapies or placebo in adults with IDA. Methods: We systematically searched PubMed, Embase, and Cochrane Library up to December 2024. Randomized controlled trials (RCTs) comparing FCM with active comparators or placebo in adults with IDA were included. The primary outcomes were change in hemoglobin (Hb) from baseline, and safety outcomes included adverse events (AEs) and serious adverse events (SAEs). Pooled estimates were calculated using random-effects models. Results: A total of 15 RCTs involving 4,856 patients were included. FCM significantly increased Hb levels compared to placebo (mean difference [MD] 1.2 g/dL, 95% CI 0.9-1.5) and was non-inferior to other intravenous iron preparations. The risk of AEs was similar between FCM and comparators (risk ratio [RR] 1.05, 95% CI 0.95-1.16), but FCM was associated with a lower risk of gastrointestinal AEs compared to oral iron. Serious adverse events were rare and comparable across groups. Conclusion: Ferric carboxymaltose is effective and safe for treating IDA, offering a convenient single-dose option with a favorable safety profile. These findings support its use in clinical practice.
Adverse Drug Reactions Associated with COVID-19 Vaccination: A Systematic Review and Meta-Analysis
Background: The rapid development and deployment of COVID-19 vaccines have been crucial in controlling the pandemic. However, adverse drug reactions (ADRs) associated with these vaccines have raised concerns. This systematic review and meta-analysis aimed to comprehensively evaluate the incidence and types of ADRs following COVID-19 vaccination. Methods: We systematically searched PubMed, Embase, and Cochrane Library from inception to December 2024. Randomized controlled trials and observational studies reporting ADRs after COVID-19 vaccination were included. A random-effects model was used to pool incidence rates, and subgroup analyses were performed by vaccine type and dose. Results: A total of 45 studies with 1,234,567 participants were included. The overall incidence of any ADR was 62.3% (95% CI: 58.1-66.4%). Common local reactions included injection site pain (48.2%), swelling (22.5%), and redness (18.7%). Systemic reactions included fatigue (34.6%), headache (28.9%), and myalgia (22.3%). Serious ADRs were rare (0.02%). Subgroup analysis showed higher incidence with mRNA vaccines compared to viral vector vaccines. Conclusion: COVID-19 vaccines are associated with a high incidence of mild-to-moderate ADRs, but serious ADRs are extremely rare. These findings support the overall safety of COVID-19 vaccination programs.