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The United States (US) as the second leading economy in global ecological pollution has become a fertile ground for a rigorous analysis of the ecological neutrality using load capacity factor (LCF) and carbon‐based consumption (CCO2). This is important for the global drive of achieving environmental sustainability by 2050. The LCF is one of the most comprehensive ecological proxies that incorporate the biocapacity and ecological footprint. In this context, this research examines the effect of natural resources, technological innovation, renewable energy and financial globalization on ecological neutrality in the US for the date spanning from 1990 to 2021. Using the novel augmented auto‐regressive distributive lag (AARDL) model, the empirical findings of this study indicate that (i) natural resources, renewable energy, and technological innovation promote ecological neutrality by increasing LCF and decreasing CCO2 emissions; (ii) financial globalization and economic growth mitigate the LCF and increase CCO2 emissions; and (iii) a causal effect is observed among technological innovation, natural resources, renewable energy, CCO2 and LCF. In light of the findings, this study recommends several crucial measures for ecological neutrality targets set out in sustainable development goals (SDGs) 7 and 13, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • Applies novel panel threshold model. • Investigates the determinants of load capacity factor for 69 countries. • The LCC hypothesis is valid for middle income countries. • FinTech, FDI, and renewable energy supports ecological progress. • Government effectiveness reduces the load capacity factor. With the evolving world order, countries are using financial technologies (Fintech) to access financial resources more effectively, and Fintech can have an impact on the environment. This study aims to investigate the influence of Fintech on ecological sustainability, focusing on the contribution of renewable energy (RE) and government effectiveness (GE) under the Load Capacity Curve (LCC). This research analyzes data from 69 middle-income economies between 2006 and 2022 using the dynamic panel threshold model (DPTR). The outcomes document that GDP reduces the LCF below a certain threshold, but a positive impact above this threshold. Specifically, the model yielded a threshold value of $US 5222.234, which is higher than the average GDP of $US 4276.802. This finding suggests a U-shaped relationship between GDP and LCF, which supports the LCC hypothesis. The outcome also reports that Fintech plays a crucial role in improving ecological sustainability, while government effectiveness has a negative effect. The study emphasizes that middle-income countries should support Fintech and renewable energy along development with economic progress to improve ecological quality. [ABSTRACT FROM AUTHOR]

Planning an immediate and multidisciplinary rehabilitation is crucial to reduce the significant physical, cognitive, and psychosocial impact resulting from head trauma. This study highlights the importance of ongoing cognitive rehabilitation in conjunction with other rehabilitation therapies, such as motor, occupational, and speech therapy, for a 19-year-old woman who suffered an acquired traumatic brain injury in a high-energy vehicle accident. When the patient was admitted to the hospital, their cognitive functioning (LCF) was 4 (confused-agitated state), their Barthel index was 0, their Glasgow coma scale (GCS) was 7, and their disability rating scale (DRS) was 7. The patient's cognitive functioning improved to LCF 8 (purposeful-appropriate), numerical rating scale: 0/10, Barthel index: 53, GCS:15, and DRS: 5 at the time of discharge from the neurorehabilitation unit. In conclusion, early cognitive intervention in a multidisciplinary rehabilitation program is essential to maximizing the patient's potential and improving the rehabilitation's outcome. [ABSTRACT FROM AUTHOR]

This study investigates the microstructural evolution and its effect on the fatigue performance of a novel nickel-based powder superalloy FGH4113A (WZ-A3) after long-term aging at 760 °C and 815 °C. The results show that long-term aging both at 760 °C and 815 °C has no significant effect on the grain size and morphology of the alloy. After aging at 760 °C for up to 2020 h, the size of the γ′ phase remains unchanged, and its morphology transitions from nearly square to nearly spherical. During long-term aging at 815 °C for 440 h, γ′ phase coarsening and spheroidizing occur simultaneously. With prolonged aging time, the size and spheroidization degree of the γ′ phase further increase. During long-term aging up to 440 h at 760 °C, the dispersed granular MC and M6C carbides dissolve and re-precipitate. By 2020 h of aging, flocculent carbides precipitate and non-continuous M6C and M23C6 accumulate at grain boundaries. After long-term aging at 815 °C for 440 h, flocculent carbides begin to precipitate within the grains. By 2020 h of aging, a large amount of flocculent carbides precipitate with significant coarsening and enrichment of the grain boundary carbides. Due to the insignificant coarsening of the γ′ phase as well as the enrichment and precipitation of the grain boundary carbides, the fatigue performance of the alloy decreases slightly after long-term aging. [ABSTRACT FROM AUTHOR]

To limit global warming to 1.5 °C, it is imperative to accelerate the global energy transition. This transition is crucial for solving the climate issue and building a more sustainable future. Therefore, within the loaded capacity curve (LCC) theory framework, this study investigates the effects of digital adaptation, energy transition, export diversification, and income inequality on the load capacity factor (LCF). This study also attempts to investigate the integration effects of digital adaptation and energy transition, and digital adaptation and export diversification, on LCF. Furthermore, we explored how income inequality influences the LCF in economies. For this study, 112 countries were selected based on the data availability. Panel data from 2010 to 2021 were analyzed using the STATA software 13 application utilizing a two-step system generalized method of moments (GMM) approach. First, interestingly, our finding shows that digital adaptation and income significantly affect the LCF. An increase in income increases the LCF among the middle-income group of countries. Therefore, LCC is confirmed in this research. Surprisingly, energy transition, export diversification, and foreign direct investment negatively impact the LCF in the base model. Second, the impact of integrating digital adaptation and energy transition has a positive effect on LCF. Third, a negative correlation was observed between the interaction of export diversification and digital adaptation with the LCF. Fourth, a positive correlation was observed between the interaction of renewable energy and digital adaptation with the LCF. Finally, this study explores the impact of the energy transition, export diversification, and income inequality on the LCF with reference to the Organization of Petroleum Exporting Countries (OPEC). The result shows a negative effect between export diversification and LCF among OPECs at a 10% significance level. To improve the quality of our planet, policymakers must understand the forces causing climate change. By adopting a comprehensive perspective, the study aims to understand how these interrelated factors collaboratively influence the LCF thoroughly. Additionally, this research seeks to provide valuable insights related to energy transition, digital adaptation, and export diversification to policymakers, researchers, and stakeholders regarding possible avenues for cultivating a more joyful and sustainable global community. [ABSTRACT FROM AUTHOR]

The increase in renewable energy penetration on the grid has accelerated the need to transition conventional fossil-based energy sources from their traditional base load operation to more flexible operational regimes. The mode of operation changed dramatically in terms of number of starts, operating hours per annum, and variation in load level. This results in greater thermal transients on operational equipment leading to an increase in Low Cycle Fatigue damage. To ensure the continued integrity of the steam turbine components, it is essential to assess the lifetime status by applying residual lifetime analysis methods. Depending on the amount of lifetime consumption and the extend of potential crack findings, different component repair options are possible. The rework or repair options can be divided into two main groups, namely, cold- and hot-rework. These two options can also be carried out consecutively. All rework or repair options provide the opportunity to improve the application of a component by applying profiling with improved stress fields and even superior materials, in the case of hot rework. The aim of the rework/reconditioning is to ensure that the steam turbine component is suitable for future operation. This ensures that plants are well placed to deliver more flexible operation in the energy industry through carefully tailored refurbishments and reworks. [ABSTRACT FROM AUTHOR]

This contribution investigates the effect of variable copper incorporation (x = 0.2, 1.0, 2.0, and 4.0) in silicate (45 SiO2, 24.5 CaO, 24.5 Na2O, 6P2O5wt%) and modified borate (45 B2O3, 24.5 CaO, 24.5 Na2O, 6P2O5wt%) bioglass materials to be used for bone bonding applications. X-ray absorption fine structure spectroscopy (XAFS) has been used to determine the oxidation states and local coordination structure of Cu atoms in silicate-based and borate-based glasses at the Cu K-edge (~ 8979 eV). The oxidation states of Cu atoms have been determined by near-edge XAFS (XANES) fingerprinting employing reference standard compounds of Cu. Cu (I) and Cu (II) XANES spectra of the standard reference compounds were linearly combined to fit the normalized μ(E) data of the collected XANES spectra using linear combination fitting (LCF approach). The obtained results prove that most of the silicate glass samples contain Cu2O almost exclusively, while modified borate glass samples contain a significant mixture of Cu2O and CuO phases. According to the literature, the remarkable coexistence of Cu2O and CuO phases within the borate sample, particularly when x = 4, promotes the conversion process to allow the more facile formation of hydroxy carbonate apatite (HCA). The best fit structural parameters derived from extended-XAFS (EXAFS) fitting show that the ratio between Cu (I) and Cu (II) in borate glass agreed well with that extracted from XANES analysis. XANES and EXAFS conclude that borate glass with x = 4 is the most suitable composition for bone bonding applications. [ABSTRACT FROM AUTHOR]

Given the alarming level of climate change, policymakers across the globe are seeking strategies to mitigate environmental pollution to achieve sustainable development. In this context, renewable energy and technological advancements have emerged as an effective way to lower pollution and attain sustainable development. This study evaluates the effect of financial inclusion, technological innovation, and renewable energy on the load capacity factor (LCF) in European countries from 2004 to 2018. LCF is considered the most comprehensive indicator of ecological sustainability, combining both the biocapacity factor and ecological footprint. Hence, the present work fills the literature gap by exploring, for the first time, the effect of financial inclusion on the LCF. Applying the advanced Method of Moment Quantile Regression (MMQR), the study demonstrates that technological innovation and economic growth have adverse effects on LCF while renewable energy and financial inclusion promote LCF. The study indicates that technological innovation and economic growth undermine ecological excellence in European nations while green energy and financial inclusion enhance it. Moreover, the findings of the causality analysis reveal a causal association between financial inclusion, renewable energy, and LCF. Our study recommends prioritizing financial inclusion alongside investments in renewable energy to enhance ecological sustainability.

Today, when climate change and environmental degradation are experienced, environmental sustainability comes to the fore. The most important component of environmental sustainability is undoubtedly technology and innovation. This study examines the effects of clean energy consumption, green innovation, and technological diffusion on environmental sustainability from 1990 to 2018 in selected European Union countries. This relationship has been frequently examined in the literature within the framework of the environmental Kuznets curve (EKC) hypothesis. The number of studies examining it within the load capacity curve (LCC) hypothesis framework is negligible. This study aims to fill the gap in the literature in the context of examining the relationship within the framework of the LCC hypothesis. For this purpose, Westerlund's (2008) panel cointegration test was applied, and cointegration was determined in the LCC model. Three different long‐term estimators, namely rCCE, DCCE, and AMG, were used to test the validity of the hypothesis. Although the results obtained for the entire panel say that the LCC hypothesis is not valid, evidence for the existence of the hypothesis has been identified in the country‐based results. Accordingly, the LCC hypothesis is valid for Denmark, France, Portugal, and Spain. Overall, green innovation and technological diffusion are essential to encourage the spread of environmentally friendly practices and to leave a more livable world for future generations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Load capacity and environmental Kuznets curve are tested for China. • We employed a novel dynamic autoregressive distributed lags model. • Renewable energy Electricity improves environmental Quality. • Load capacity and environmental Kuznets curve exist for China. • The study provides relevant policy implications in this regard. Climate changes are occurring faster than expected and affecting human lives through increasing carbon emissions, food scarcity and changes in global temperatures. Following this trend, China is one of the top contributors to global pollution, and at the same time, it is a leading producer of electricity production from renewable sources (ELREC). The current research examines the relationship between ELREC, research and development (REDEV), and economic growth and their impact on three environmental quality indicators: carbon dioxide emissions, ecological footprint, and load capacity factor in China from 1985 to 2018. This research is significant because it helps to identify factors contributing to the environmental deterioration in China and how they can be addressed. Using the autoregressive distributed lag and dynamic autoregressive distributed lag model, the research suggests a load capacity curve (LCC) and simultaneously tests the LCC and environmental Kuznets curve (EKC) hypotheses. The findings indicate that the LCC and EKC hypotheses are viable in China and that ELREC favorably influences environmental quality. Additionally, REDEV has a significant impact on environmental indicators. The findings of this research reveal, in general, that sustainable REDEV, prioritizing environmental protection, and transitioning towards renewable energy sources are crucial elements of China's green development strategy. This study's findings provide valuable insights for policymakers and stakeholders working to improve environmental quality in China. [ABSTRACT FROM AUTHOR]

[Display omitted] • The study examines nuclear and hydro electricity consumption impact on environment. • The study focuses on leading 8 nuclear countries for the period 1995/Q1-2018/Q4. • The study uses novel non-linear quantile approaches. • Nuclear energy consumption has an improving impact on environmental quality. • Hydroelectricity consumption has a degrading on environmental quality. • The results vary based on energy types, countries, and quantiles. This research examines the impacts of nuclear energy consumption (NEC) and hydro electricity consumption (HEC) on environmental quality. In doing so, the study examines eight leading NEC countries representing 80% of total NEC by considering also impacts of HEC, using load capacity factor (LCF) as the most comprehensive environment indicator, and including data between 1995/Q4 and 2018/Q4 as the most recent available intersect data. Besides, quantile-on-quantile regression (QoQR) and Granger causality-in-quantiles (GCiQ) approaches are applied as base models and quantile regression (QR) is considered for robustness. The outcomes present that (i) NEC and HEC have a causal impact on the LCF; (ii) NEC has a generally increasing impact on the LCF at high levels of NEC in all countries except for France and the United States of America (USA); (iii) HEC has a generally decreasing impact on the LCF at high levels of NEC in all countries except for USA and Germany; (iv) the impacts of NEC and HEC on the LCF change according to countries and levels (i.e., quantiles) of NEC and HEC; (v) the QR approach validates the robustness of the outcomes. Hence, the outcomes highlight the significant impact of nuclear (hydro electricity) energy consumption in increasing (decreasing) environmental quality and the importance of quantile and country based analyses. Furthermore, based on the empirical outcomes, policy inferences are discussed. [ABSTRACT FROM AUTHOR]

This pragmatic randomized controlled trial compared lunocapitate fusion (LCF) and four-corner fusion (4CF) for scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) in 64 patients. The primary outcome was change in grip strength from preoperative to 1 year postoperatively. The secondary outcomes were Disability of the Hand, Arm, and Shoulder score, Patient Rated Wrist Evaluation score, EuroQol-5D-3L, range of motion, key pinch strength and complications 12 months postoperatively. Grip strength improved only to a small extent and there was no difference between the groups. No differences were found in the secondary outcomes. In conclusion, LCF is not inferior to 4CF regarding strength, range of motion or patient-reported outcome measures. [ABSTRACT FROM AUTHOR]

Planning an immediate and multidisciplinary rehabilitation is crucial to reduce the significant physical, cognitive, and psychosocial impact resulting from head trauma. This study highlights the importance of ongoing cognitive rehabilitation in conjunction with other rehabilitation therapies, such as motor, occupational, and speech therapy, for a 19-year-old woman who suffered an acquired traumatic brain injury in a high-energy vehicle accident. When the patient was admitted to the hospital, their cognitive functioning (LCF) was 4 (confused-agitated state), their Barthel index was 0, their Glasgow coma scale (GCS) was 7, and their disability rating scale (DRS) was 7. The patient’s cognitive functioning improved to LCF 8 (purposeful-appropriate), numerical rating scale: 0/10, Barthel index: 53, GCS:15, and DRS: 5 at the time of discharge from the neurorehabilitation unit. In conclusion, early cognitive intervention in a multidisciplinary rehabilitation program is essential to maximizing the patient’s potential and improving the rehabilitation’s outcome.

Investigating the distribution of different Zn species on Zn-containing zeolite catalysts is crucial for identifying the active sites and establishing the relationship between the catalyst's structure and its activity in the process of ethylene aromatization. By utilizing X-ray absorption near edge spectra (XANES) of various reference samples, this study employed linear combination fitting (LCF) analysis on XANES spectra of real samples to accurately measure the changes in the distribution of Zn species in Zn-containing HZSM-5 zeolites under different Zn sources and loadings. The results showed that ZnOH+, ZnO clusters, and ZnO crystalline structures coexist in Zn/HZSM-5 catalysts prepared through physical mixing and incipient wet impregnation methods. A similar trend was observed for catalysts prepared using different methods, with an increase in Zn content resulting in a decrease in the proportion of ZnOH+ and a significant increase in the amount of larger ZnO crystals. Furthermore, ZnO clusters were confined within the zeolite pores. The findings of this study established a direct correlation between the amount of ZnOH+ determined through LCF analysis and both the rate of hydrogen production and the rate of aromatics formation, providing strong evidence for the catalytic role of ZnOH+ as an active center for dehydrogenation, which plays a key role in promoting the formation of aromatics. The method of LCF analysis on XANES spectra allows for the determination of the local structure of Zn species, facilitating a more precise analysis based on the distribution of these species. This method not only provides detailed information about the Zn species but also enhances the accuracy of the overall analysis. [ABSTRACT FROM AUTHOR]

Most countries have tried to decline fossil fuels dependency by supporting clean energy transition. In light of this, this study investigates the impact of energy security risk (ESR) and geopolitical risk (GPR) on the load capacity factor (LCF) in four fragile countries (Brazil-BRA; India-IND; South Africa-ZAF, Türkiye-TUR). The study applies quantile approaches for the period between 1985/m2 and 2018/m12, which represents the largest amount of accessible data. The results show that (i) at higher quantiles, ESR declines the LCF in IND and ZAF, while it has an increasing impact in BRA and a mixed impact in TUR; (ii) GPR increases the LCF in BRA, ZAF, and TUR at lower and middle quantiles, while GPR decreases ecological quality at higher quantiles in all countries; (iii) ESR and GPR have a causal effect on the LCF across various quantiles; (iv) ESR and GPR are strong predictors of the LCF, but their predictive power varies by quantile and becomes significantly weaker with increasing lags. With these fresh outcomes, the study underlines the significant influence of ESR and GPR in ensuring ecological sustainability across all quantiles and countries. The overall findings of the study emphasize that risks and uncertainties degrade the ecological quality of four fragile countries and that policymakers should turn to clean energy sources in case of an increase in geopolitical and energy risks.

In this work, cast steel G17CrMoV5-10 was investigated. The material subject to investigation as part of this study is commonly used to manufacture steam turbine casings. Modern steam turbines operate under elevated temperature and complex oscillated loads. Thus, the focus of this study was to investigate material under behavior during low cycle fatigue (LCF) test performance at 500°C with and without hold time in tension. During all types of test, cyclic softening of cast steel was noticed. Increasing of total strain rate and applying hold time significantly reduce fatigue life. During hold time, due to temperature and tension the material creep what is confirmed by increasing inelastic stain accommodation.

To limit global warming to 1.5 °C, it is imperative to accelerate the global energy transition. This transition is crucial for solving the climate issue and building a more sustainable future. Therefore, within the loaded capacity curve (LCC) theory framework, this study investigates the effects of digital adaptation, energy transition, export diversification, and income inequality on the load capacity factor (LCF). This study also attempts to investigate the integration effects of digital adaptation and energy transition, and digital adaptation and export diversification, on LCF. Furthermore, we explored how income inequality influences the LCF in economies. For this study, 112 countries were selected based on the data availability. Panel data from 2010 to 2021 were analyzed using the STATA software 13 application utilizing a two-step system generalized method of moments (GMM) approach. First, interestingly, our finding shows that digital adaptation and income significantly affect the LCF. An increase in income increases the LCF among the middle-income group of countries. Therefore, LCC is confirmed in this research. Surprisingly, energy transition, export diversification, and foreign direct investment negatively impact the LCF in the base model. Second, the impact of integrating digital adaptation and energy transition has a positive effect on LCF. Third, a negative correlation was observed between the interaction of export diversification and digital adaptation with the LCF. Fourth, a positive correlation was observed between the interaction of renewable energy and digital adaptation with the LCF. Finally, this study explores the impact of the energy transition, export diversification, and income inequality on the LCF with reference to the Organization of Petroleum Exporting Countries (OPEC). The result shows a negative effect between export diversification and LCF among OPECs at a 10% significance level. To improve the quality of our planet, policymakers must understand the forces causing climate change. By adopting a comprehensive perspective, the study aims to understand how these interrelated factors collaboratively influence the LCF thoroughly. Additionally, this research seeks to provide valuable insights related to energy transition, digital adaptation, and export diversification to policymakers, researchers, and stakeholders regarding possible avenues for cultivating a more joyful and sustainable global community.

Symmetrical high‐temperature low‐cycle fatigue tests were performed in this study to examine the influence of temperature on the fatigue failure mechanism of the additively manufactured Inconel 625. According to the fracture analysis, cracks initiate from the crystallographic plane at room temperature. At 600°C, oxidation of carbides leads to crack initiation. The strengthening effect of γ″ precipitation prevents crack propagating within the matrix. At 750°C, the crack becomes transgranular propagating, as a consequence of γ″‐δ transformation. Geometrically necessary dislocations distribution on the fracture supports this result. Furthermore, a modified life prediction formula considering effect of temperature and strain amplitude was established. It was observed that the modified model predicted the fatigue life of the studied materials well in both test conditions. Highlights: Cracks initiate from favorable slip plane at room temperature.Precipitation of γ″ at 650°C prevents dislocation shearing into the matrix.Cyclic plastic deformation accelerates the γ″‐δ transformation at 700°C.Life prediction model considering strain amplitude and temperature shows good accuracy. [ABSTRACT FROM AUTHOR]

The influence of pre‐strain on the tensile and fatigue properties of a dual phase DP600 steel was studied. The material was pre‐strained by uni‐axial tension in rolling and transverse direction. Thereafter, specimens were cut from the deformed plates in parallel or orthogonal to pre‐strain direction. It was found that pre‐strain increases yield and tensile strength. Results suggested that strain path change primarily affects the elastic‐plastic transition during early stage of reloading. Pre‐strained specimens showed an increase in high cycle regimes as a consequence of yield strength increment, irrespective of imposed pre‐straining direction. A modified stress life equation that accounts for pre‐strain was proposed and showed good agreement with experimental data. Bake hardening enhanced both tensile and high cycle fatigue resistance. Walker equation was successfully fitted to account for tensile mean stress. In low cycle fatigue, negligible influence of pre‐strain was observed due to cyclic softening and residual stress relaxation. Highlights: A DP600 steel sheet is characterized under different pre‐strain conditions and after baking.Experiments indicate that pre‐strain and bake hardening are beneficial in HCF.Modified Basquin equations to account for the effect of pre‐strain and bake hardening are proposed.Walker mean stress correction shows good agreement with experimental data. [ABSTRACT FROM AUTHOR]

AZ91 is one of the most broadly used Mg alloys because of its good castability and reasonable mechanical properties. Strengthening AZ91 with carbon short fibers aims to increase tensile and fatigue strength, creep, and wear resistance. One of the proposed applications of reinforced AZ91 is the production of pistons for trucks. Such reciprocating parts are subjected to alternating fatigue loads which can lead to fatigue failure. In this respect, studying the tensile and fatigue behavior of materials subjected to such loading conditions is of great interest. The alternating low-cycle fatigue (LCF) and high-cycle fatigue (HCF) of unreinforced AZ91 and carbon fiber-reinforced AZ91 (AZ91-C) were investigated at 20 °C and 250 °C. Tensile tests were carried out at the same testing temperature to find the appropriate fatigue testing stress and strain for stress-controlled and strain-controlled tests, respectively. The fatigue curves of stress against the number of cycles (S–N) revealed that the composite AZ91-C's fatigue strength was 55 MPa under HCF, while that of the matrix alloy AZ91 was only 37 MPa at 250 °C. Fracture investigations were conducted on the broken test samples. The fracture approach in the matrix material (AZ91) is mixed ductile/brittle containing fatigue serration, fiber fracture, and separation in the reinforced material (AZ91-C). [ABSTRACT FROM AUTHOR]

This study investigates four different joints under fluctuating tension cycles in the low-cycle fatigue (LCF) regime. The selected material was S960 ultra-high-strength steel, manufactured via the direct-quenching manufacturing route. Based on typical engineering solutions, the following joints were chosen to be investigated in the experimental tests: metal active gas and laser welded butt joints, fillet-welded load-carrying cruciform joints, and non-load-carrying double-sided transverse attachment joints. To evaluate the improvement gained by the post-weld treatment, both as-welded condition and high-frequency mechanical impact treated joints from all joint types were tested. In addition to the experimental tests, some of the joints were analyzed using finite element (FE) models, with the aim of comparing the accuracy of the different fatigue assessment methods and the effect of the toe radius on the computational fatigue lives. The results obtained from the experimental tests and FE analyses were compared with each other and with IIW recommendations using the nominal stress, structural hot-spot (HS) stress, effective notch stress (ENS) and 4R methods. Based on the results, the structural HS and 4R methods are very suitable for the fatigue strength assessment in the LCF regime. With the nominal stress method, the computational fatigue lives remained uniformly conservative, while with the ENS method, the results varied depending on the calculation method. Using the value r = 1 mm as the weld toe rounding is justified in the FE analysis. [ABSTRACT FROM AUTHOR]

• Analyzing the Impact of NEC and REC on LCF and EFP in Russia. • ARDL is used to analyze NEC and REC effects on the LCF and EFP. • EKC and LCC Hypothesis are validated for EFP and LCF, showing positive impact of NEC and REC on environment. • Nuclear energy improves LCF, while renewables positively impact the environment in the short and long run. The purpose of this research is to investigate the effects of nuclear and renewable energy usage on the environment in Russia, using a unique approach that emphasizes two important variables: ecological footprint and load capacity factor. The study employs autoregressive distributed lag (ARDL) analysis to examine the relationship between energy consumption and environmental degradation, using data from 1992 to 2018. The study tests two hypotheses simultaneously: the environmental Kuznets curve (EKC) and the load capacity curve (LCC). The findings reveal that renewable energy has both short-term and long-term environmental benefits, as these positive effects are indicated on both the LCF and EFP. In addition, Nuclear energy usage leads to a reduction in ecological footprint in both the short and long run. Although nuclear energy has negligible short-term effects on the load capacity factor, it has significant positive long-term effects. The study concludes that both nuclear and renewable energy can help improve environmental quality in Russia and provides evidence for the presence of both the load capacity curve (LCC) and the environmental Kuznets curve (EKC) hypotheses. [ABSTRACT FROM AUTHOR]

The National Transportation Safety Board investigated two accidents involving fan blade fatigue fractures in CFM International CFM56-7B engines. Fatigue cracks developed in the Ti–6Al–4V blades in an area of high contact stresses in the dovetail. Additional cracked blades were found using nondestructive inspections developed after the first accident. Although the blades had been shot peened, many of the blades had relaxed compressive residual stress profiles at the surface, making them more susceptible to fatigue crack initiation under the combined effects of loading/friction changes over time, coating condition, surface condition, and engine operational differences. Flight cycle estimates based on striation counting on the fracture surfaces revealed that blades with normal residual stress profiles had been overhauled after cracks had initiated, masking the original surface condition. As a result of investigation findings, new procedures were developed, including more frequent dovetail lubrications, improved visual inspection procedures, and new ultrasonic testing and eddy current procedures, which were implemented to reduce contact stresses in the dovetail and to detect any potential cracks that might develop in the dovetail before blade fracture. [ABSTRACT FROM AUTHOR]

Lightweight magnesium alloys and magnesium matrix composites have recently become more widespread for high-efficiency applications, including automobile, aerospace, defense, and electronic industries. Cast magnesium and magnesium matrix composites are applied in many highly moving and rotating parts, these parts can suffer from fatigue loading and are consequently subjected to fatigue failure. Reversed tensile-compression low-cycle fatigue (LCF) and high-cycle fatigue (HCF) of short fibers reinforced and unreinforced AE42 have been studied at temperatures of 20 °C, 150 °C, and 250 °C. To select suitable fatigue testing conditions, tensile tests have been carried out on AE42 and the composite material AE42-C at temperatures of up to 300 °C. The Wohler curves σa (NF) have shown that the fatigue strength of the reinforced AE42-C in the HCF range was double that of unreinforced AE42. In the LCF range at certain strain amplitudes, the fatigue life of the composite materials is much less than that of the matrix alloys, this is due to the low ductility of this composite material. Furthermore, a slight temperature influence up to 150 °C has been established on the fatigue behavior of the AE42-C. The fatigue life curves Δεtotal (NF) were described using the Basquin and Manson–Coffin approaches. Fracture surface investigations showed a mixed mode of serration fatigue pattern on the matrix and carbon fibers fracturing and debonding from the matrix alloy. [ABSTRACT FROM AUTHOR]

The fatigue and creep–fatigue properties of 316SS formed by selective laser melting (SLM) were investigated, considering the effects of different peak stresses, stress rates and peak-holding times on the ratcheting and creep-ratcheting behaviour of SLM 316 SS specimens at different sampling angles (0°, 90°) and high temperatures (550°C, 650°C, 750°C). Results show that the 90° specimens exhibited better fatigue life than that of the 0° specimens. Moreover, the ratcheting evolution can be divided into three stages, but the first stage is very short and the main ratcheting behaviour takes place in the second and third stages. Interestingly, it was found that at stress rates above 10 MPa/s, the ratcheting evolution curves are highly overlapping. Furthermore, the creep–fatigue interaction promotes the evolution of material damage. Besides, creep increases the total strain of 316SS even with a short dwell time (0.5 min). [ABSTRACT FROM AUTHOR]

Investigating the distribution of different Zn species on Zn-containing zeolite catalysts is crucial for identifying the active sites and establishing the relationship between the catalyst’s structure and its activity in the process of ethylene aromatization. By utilizing X-ray absorption near edge spectra (XANES) of various reference samples, this study employed linear combination fitting (LCF) analysis on XANES spectra of real samples to accurately measure the changes in the distribution of Zn species in Zn-containing HZSM-5 zeolites under different Zn sources and loadings. The results showed that ZnOH+, ZnO clusters, and ZnO crystalline structures coexist in Zn/HZSM-5 catalysts prepared through physical mixing and incipient wet impregnation methods. A similar trend was observed for catalysts prepared using different methods, with an increase in Zn content resulting in a decrease in the proportion of ZnOH+ and a significant increase in the amount of larger ZnO crystals. Furthermore, ZnO clusters were confined within the zeolite pores. The findings of this study established a direct correlation between the amount of ZnOH+ determined through LCF analysis and both the rate of hydrogen production and the rate of aromatics formation, providing strong evidence for the catalytic role of ZnOH+ as an active center for dehydrogenation, which plays a key role in promoting the formation of aromatics. The method of LCF analysis on XANES spectra allows for the determination of the local structure of Zn species, facilitating a more precise analysis based on the distribution of these species. This method not only provides detailed information about the Zn species but also enhances the accuracy of the overall analysis.

γ-Irradiation and synchrotron-radiation-based X-ray absorption fine-structure (XAFS) spectroscopy have been used to induce structure disorder through the interaction of γ-rays (200 kGy) with fabricated Mn-doped ZnO nanoparticles (NPs) and then to examine thoroughly the resultant structural change. The extracted electronic/fine XAFS structural parameters reflect a compositional and γ-irradiation co-dependence. The average crystal structure of samples prepared by the sol-gel method was investigated by X-ray diffraction (XRD). A detailed structural XRD data analysis was carried out by applying a Rietveld refinement using the MAUD program. XAFS spectra were collected at the Zn K-edge (9659 eV) in transmission mode and at the Mn K-edge (6539 eV) in fluorescence mode. Direct evidence of the solubility of Mn ions in the ZnO structure was demonstrated by fitting the extended-XAFS (EXAFS) signal. Near-edge XAFS (XANES) analysis provided the oxidation states of Zn and Mn ions through fingerprint XANES spectra of the sample along with those of standard compounds. Linear combination fitting showed that the most fit chemical forms of Zn and Mn in the samples are ZnO and MnO, respectively. The oxidation states of both Zn and Mn XAFS absorbers were confirmed from pre-edge fitting. The results of the magnetic measurements were explained in light of the average and electronic/local structural information obtained from XRD, XANES and EXAFS techniques. The magnetic properties of the samples translate into an induced change in the average crystal and electronic/local structures upon Mn concentration change and γ-irradiation. XRD confirmed the successful preparation of hexagonal Mn-doped ZnO NPs with a crystallite size in the range 33–41 nm. Both XRD and EXAFS analysis detected a minor amount of Mn3O4 as a secondary phase. XANES and EXAFS provided information exploring the outstanding potential of the utilized protocol for detecting precisely the presence of the secondary phase of Mn3O4, which changes with Mn content (x). Mean-square relative displacement (σ2) values extracted from the EXAFS fitting were found to grow for Zn–Zn/Mn paths demonstrating the substitution of Mn/Zn into Zn crystal sites. The EXAFS analysis explains the reasons behind the enhancement in the magnetic properties and shows that the Mn doping content at x = 0.05 produces the most local atomic disorder in ZnO NPs. There is a strong harmony among the XRD, XANES, EXAFS and magnetization behavior of the Mn-doped ZnO NPs. Maximum magnetization was acquired at an Mn content of 0.05. γ-Ray-irradiated Zn1–xMnxO NPs are recommended as optimized candidates for showing the diversity of the applications.

As is well-known, non-proportional fatigue loading, such as asynchronous one, can have significant detrimental effects on the fatigue behavior of metallic materials by reducing the fatigue strength/fatigue limit and by leading to a fatigue damage accumulation increased with respect to that under proportional loading. In the present paper, the novel refined equivalent deformation (RED) criterion is applied for the first time to estimate the fatigue lifetime of materials, sensitive to non-proportionality, subjected to asynchronous loading under low-cycle fatigue regime. The present criterion is complete since it considers: (i) the strain path orientation, (ii) the degree of non-proportionality, and (iii) the changing of material cyclic properties under non-proportional loading. To evaluate its accuracy, this criterion is applied to examine two different metals (a 304 stainless steel and a 355 structural steel) whose experimental data under multiaxial asynchronous loading are available in the literature. More precisely, the parameters of the criterion are firstly determined by using experimental strain paths, and then the computed refined equivalent deformation amplitude is used to represent the experimental data with a satisfactory accuracy. Finally, a comparison with the results obtained through two other criteria available in the literature is performed, highlighting the good prediction of the present RED criterion. [ABSTRACT FROM AUTHOR]

The growth of financial services has been critical in Turkey's pursuit of economic growth objectives throughout the last two decades. Nevertheless, it cannot be denied that it has a negative impact on environmental quality. Based on this, in the current paper, the effect of energy use, trade openness, and financial development on the load capacity factor (LCF) is explored for Turkey between 1965 and 2018. In doing so, a series of quantile approaches such as quantile cointegration (QC), quantile-on-quantile regression (QQR), nonparametric causality-in-quantiles (NCQ), and quantile regression (QR) are used. The results generated from the QQR and also validated by the QR reveal that in the majority of the quantiles, primary energy use, trade openness, and financial development impact the LCF negatively. These results suggest that primary energy use, trade openness, and financial development damage environmental quality. Furthermore, the findings gathered from the quantile causality disclose that all primary energy use, trade openness, and financial development can forecast LCF in the majority of the quantiles. Based on the research outcomes, policies, which may aid to solve the damaging environmental effects of the primary energy use, trade openness, and financial sector development in Turkey are recommended. [ABSTRACT FROM AUTHOR]

A numerical turbine-blade fatigue-life analysis method is suggested. This method comprises a stationary thermal 3D finite element (FE) analysis of the hot run for the combined high-cycle fatigue (HCF) and creep analysis, and a follow-on (one-way coupled) quasi-stationary structural 3D FE analysis (including six load steps) of a single and two half turbine blades and the related disk and rotor section and a (modified Goodman equation based) post-processing fatigue life analysis for the highest HCF-loaded point of the turbine blade. For the low-cycle fatigue (LCF) analysis, this includes a transient thermal 3D FE analysis of two full loading cycles, a follow-on (one-way coupled) quasi-stationary structural 3D finite element analysis of a single and two half turbine blades and the related disk and rotor section and a (modified-Langer-equation-based) post-processing fatigue life analysis approach for the highest LCF-loaded point of the turbine blade. Finally, this approach is demonstrated by the numerical HCF, LCF and creep analysis of a generic turbine blade of the first rotor row of a full admission hydrogen turbo pump of a 1 MN thrust class gas generator LOX-LH2 liquid rocket engine (LRE). For this numerical example, the LCF loading turned out to be dominant. Creep turned out to be negligible. [ABSTRACT FROM AUTHOR]

Chronic ankle instability is a common issue in high-level athletes, affecting up to 48 % of lateral sprains. Rehabilitation strategies, including muscle strengthening, proprioceptive training, and range of motion exercises, often help but may not suffice, especially in sports that stress the ankle in a varus position. In such cases, surgery is required. Non-anatomic techniques have shown long-term ineffectiveness, while anatomical reconstructions with tissue augmentation are gaining favor. This study introduces the underreported ALL (Ankle Lateral Ligamentoplasty) technique, using gracilis tendon transfer for chronic ankle instability. This minimally invasive method restores the ruptured lateral collateral ligaments and preserves proprioceptive and anatomical stability, with the added benefit of sparing the semitendinosus tendon for potential knee surgery. The surgical procedure allows immediate walking post-op with progressive recovery, including early mobilization, brace use by the fourth week, and return to pivot sports by the third month. Compared to tenodesis procedures, anatomical reconstruction offers superior stability and mobility, faster recovery, and less risk of degenerative arthritis. The ALL technique shows promise in treating chronic ankle instability in athletes, providing effective stabilization while preserving ankle function. However, further studies are needed to validate its widespread clinical use. • Chronic Ankle Instability: A major issue for athletes, often requiring more than just rehab. • Surgical Approaches: Anatomical reconstructions are now favored over non-anatomical methods. • Study Focus: Introducing the ALL (Ankle Lateral Ligamentoplasty) technique using gracilis tendon transfer. • Unique Advantages: ALL offers stability and preserves the potential for future knee surgeries. • Surgical Benefits: Faster recovery and return to sports, though it's not widely documented yet. [ABSTRACT FROM AUTHOR]

AZ91 is one of the most broadly used Mg alloys because of its good castability and reasonable mechanical properties. Strengthening AZ91 with carbon short fibers aims to increase tensile and fatigue strength, creep, and wear resistance. One of the proposed applications of reinforced AZ91 is the production of pistons for trucks. Such reciprocating parts are subjected to alternating fatigue loads which can lead to fatigue failure. In this respect, studying the tensile and fatigue behavior of materials subjected to such loading conditions is of great interest. The alternating low-cycle fatigue (LCF) and high-cycle fatigue (HCF) of unreinforced AZ91 and carbon fiber-reinforced AZ91 (AZ91-C) were investigated at 20 °C and 250 °C. Tensile tests were carried out at the same testing temperature to find the appropriate fatigue testing stress and strain for stress-controlled and strain-controlled tests, respectively. The fatigue curves of stress against the number of cycles (S–N) revealed that the composite AZ91-C’s fatigue strength was 55 MPa under HCF, while that of the matrix alloy AZ91 was only 37 MPa at 250 °C. Fracture investigations were conducted on the broken test samples. The fracture approach in the matrix material (AZ91) is mixed ductile/brittle containing fatigue serration, fiber fracture, and separation in the reinforced material (AZ91-C).

Experiments have been performed to investigate the strain-controlled low cyclic fatigue (LCF) behavior and cyclic behavior of ratcheting of annealed austenitic stainless steel. While LCF experiments have been carried out under completely reversed straining conditions at a range between +/–0.375 and +/–1.00% of five strain amplitudes, experiments have been performed to observe the mean stress effect on the cyclic behavior of ratcheting of the solution annealed austenitic stainless steel (AISI 304) for 1000 cycles keeping the stress amplitude constant. The present study also looks into the cyclic ratcheting effect on the LCF behavior of the steel. Results of LCF and ratcheting tests have been analyzed to observe the LCF resistance of the investigated steel and to understand the response of the steel to the interaction of ratcheting fatigue. [ABSTRACT FROM AUTHOR]

We present a probabilistic model for quantifying the number of load cycles for nucleation of forging flaws--for a 3.5NiCrMoV high strength low alloy rotor steel--into a crack under gas turbine operating conditions. The model correlates low cycle fatigue data, ultrasonic testing indication data, flaw morphology, and type with the nucleation process. This paper is the third of a series of publications presenting this modeling approach progressively. It focuses on the effect of temperature variation on the nucleation life of forging flaws. We quantified the number of cycles to crack nucleation was for specimens that included forging flaws at elevated temperatures. Flaws of different sizes and shapes are effectively described at respective temperature and stress levels by either an ellipsoidal finite element model or an analytical area-based model. A local probabilistic low-cycle fatigue model analyzes the resulting stress distributions accounting for statistical size effects. Via Maximum Likelihood Estimation of these probabilistic low cycle fatigue results, a probabilistic model for crack nucleation of forging flaws is obtained. This proposed probabilistic model is based on experimental data for realistic heavy duty gas turbine rotor temperature and stress conditions. It can be utilized in the energy sector for component life time quantification. Our suggested approach can support component assessment under flexible gas turbines operation conditions driven by increased availability of intermittent renewable energy sources. [ABSTRACT FROM AUTHOR]

Given the alarming level of climate change, policymakers across the globe are seeking strategies to mitigate environmental pollution to achieve sustainable development. In this context, renewable energy and technological advancements have emerged as an effective way to lower pollution and attain sustainable development. This study evaluates the effect of financial inclusion, technological innovation, and renewable energy on the load capacity factor (LCF) in European countries from 2004 to 2018. LCF is considered the most comprehensive indicator of ecological sustainability, combining both the biocapacity factor and ecological footprint. Hence, the present work fills the literature gap by exploring, for the first time, the effect of financial inclusion on the LCF. Applying the advanced Method of Moment Quantile Regression (MMQR), the study demonstrates that technological innovation and economic growth have adverse effects on LCF while renewable energy and financial inclusion promote LCF. The study indicates that technological innovation and economic growth undermine ecological excellence in European nations while green energy and financial inclusion enhance it. Moreover, the findings of the causality analysis reveal a causal association between financial inclusion, renewable energy, and LCF. Our study recommends prioritizing financial inclusion alongside investments in renewable energy to enhance ecological sustainability., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

γ-Irradiation and synchrotron-radiation-based X-ray absorption fine-structure (XAFS) spectroscopy have been used to induce structure disorder through the interaction of γ-rays (200 kGy) with fabricated Mn-doped ZnO nanoparticles (NPs) and then to examine thoroughly the resultant structural change. The extracted electronic/fine XAFS structural parameters reflect a compositional and γ-irradiation co-dependence. The average crystal structure of samples prepared by the sol-gel method was investigated by X-ray diffraction (XRD). A detailed structural XRD data analysis was carried out by applying a Rietveld refinement using the MAUD program. XAFS spectra were collected at the Zn K-edge (9659 eV) in transmission mode and at the Mn K-edge (6539 eV) in fluorescence mode. Direct evidence of the solubility of Mn ions in the ZnO structure was demonstrated by fitting the extended-XAFS (EXAFS) signal. Near-edge XAFS (XANES) analysis provided the oxidation states of Zn and Mn ions through fingerprint XANES spectra of the sample along with those of standard compounds. Linear combination fitting showed that the most fit chemical forms of Zn and Mn in the samples are ZnO and MnO, respectively. The oxidation states of both Zn and Mn XAFS absorbers were confirmed from pre-edge fitting. The results of the magnetic measurements were explained in light of the average and electronic/local structural information obtained from XRD, XANES and EXAFS techniques. The magnetic properties of the samples translate into an induced change in the average crystal and electronic/local structures upon Mn concentration change and γ-irradiation. XRD confirmed the successful preparation of hexagonal Mn-doped ZnO NPs with a crystallite size in the range 33-41 nm. Both XRD and EXAFS analysis detected a minor amount of Mn3O4 as a secondary phase. XANES and EXAFS provided information exploring the outstanding potential of the utilized protocol for detecting precisely the presence of the secondary phase of Mn3O4, which changes with Mn content (x). Mean-square relative displacement (σ2) values extracted from the EXAFS fitting were found to grow for Zn-Zn/Mn paths demonstrating the substitution of Mn/Zn into Zn crystal sites. The EXAFS analysis explains the reasons behind the enhancement in the magnetic properties and shows that the Mn doping content at x = 0.05 produces the most local atomic disorder in ZnO NPs. There is a strong harmony among the XRD, XANES, EXAFS and magnetization behavior of the Mn-doped ZnO NPs. Maximum magnetization was acquired at an Mn content of 0.05. γ-Ray-irradiated Zn1-xMnxO NPs are recommended as optimized candidates for showing the diversity of the applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Environmental impacts of green R&D expenditures analyzed. • Augmented ARDL and Fourier Toda-Yamamoto methods applied. • Green R&D expenditures leads to environmental improvements. • Financial development and population density raise the load capacity factor. • The load capacity curve hypothesis is valid. Renewable energy, energy efficiency, and nuclear energy research and development (RER, EER, and NER) budgets are immensely important to fulfill sustainable development goals 7, 9, and 13, by accelerating energy innovation, energy transition, and climate control. The literature on the drivers of the load capacity factor (LCF), a recently developed ecological quality measure, is mounting; however, the roles of energy investments in the LCF are largely unknown. Accordingly, this study assesses the impacts of RER, EER, NER, and financial globalization (FIG) on the LCF using data from 1974 to 2018 for Germany. Advanced and reliable time series tests (Augmented ARDL, DOLS, and Fourier causality) are adopted to analyze cointegration, long-run impacts, and causal connections. The outcomes unveil that both green energy and energy efficiency R&D promote the LCF by enhancing ecological quality. However, the positive impact of NER on the LCF is found to be weaker than the impacts of RER and EER. FIG curbs ecological degradation by expanding the LCF. Additionally, the U-shaped connection between economic growth (ECG) and the LCF confirms the load capacity curve. Therefore, policymakers should focus on RER and EER to preserve the environment and promote sustainable growth. [ABSTRACT FROM AUTHOR]

The multi-source fatigue crack growth characteristics of a turbine disk were studied via high-speed rotating low cycle fatigue test, fracture analysis and crack growth simulation analysis. The results show that the fatigue initiation life N0 of Superalloy disk and its simulation parts is less dispersive and similar, and the S-N0 curve of the material is not conservative to predict the N0 of the disk. The fracture of eccentric hole of disk is multi-source fatigue fracture, and the surface characteristic of the crack L/D decreases rapidly from 7.5 to 2, which is obviously different from the single source fatigue crack growth. Because of the long and thin stress distribution at the eccentric hole and the small dispersivity of GH698 crack initiation life, it's relatively easy to crack on the plane A of the eccentric hole, which is prone to multi-source fatigue. At the stage of a ≥ 1.23 mm, the reverse life of crack propagation fracture of 2# and 5# eccentric holes is consistent, and the error between the simulation value of single source fatigue crack propagation life and the reverse life is below 5%. In the stage of 0.61 mm ≤ a < 1.23 mm, the simulation crack growth rate of 5# eccentric hole of multi-source is close to that of fracture inversion. Accurate simulation analysis of multi-source crack growth needs to define the initial crack accurately, at the same time, consider the influence of existing fatigue damage on crack growth.

As is well-known, non-proportional fatigue loading, such as asynchronous one, can have significant detrimental effects on the fatigue behavior of metallic materials by reducing the fatigue strength/fatigue limit and by leading to a fatigue damage accumulation increased with respect to that under proportional loading. In the present paper, the novel refined equivalent deformation (RED) criterion is applied for the first time to estimate the fatigue lifetime of materials, sensitive to non-proportionality, subjected to asynchronous loading under low-cycle fatigue regime. The present criterion is complete since it considers: (i) the strain path orientation, (ii) the degree of non-proportionality, and (iii) the changing of material cyclic properties under non-proportional loading. To evaluate its accuracy, this criterion is applied to examine two different metals (a 304 stainless steel and a 355 structural steel) whose experimental data under multiaxial asynchronous loading are available in the literature. More precisely, the parameters of the criterion are firstly determined by using experimental strain paths, and then the computed refined equivalent deformation amplitude is used to represent the experimental data with a satisfactory accuracy. Finally, a comparison with the results obtained through two other criteria available in the literature is performed, highlighting the good prediction of the present RED criterion.

A numerical turbine-blade fatigue-life analysis method is suggested. This method comprises a stationary thermal 3D finite element (FE) analysis of the hot run for the combined high-cycle fatigue (HCF) and creep analysis, and a follow-on (one-way coupled) quasi-stationary structural 3D FE analysis (including six load steps) of a single and two half turbine blades and the related disk and rotor section and a (modified Goodman equation based) post-processing fatigue life analysis for the highest HCF-loaded point of the turbine blade. For the low-cycle fatigue (LCF) analysis, this includes a transient thermal 3D FE analysis of two full loading cycles, a follow-on (one-way coupled) quasi-stationary structural 3D finite element analysis of a single and two half turbine blades and the related disk and rotor section and a (modified-Langer-equation-based) post-processing fatigue life analysis approach for the highest LCF-loaded point of the turbine blade. Finally, this approach is demonstrated by the numerical HCF, LCF and creep analysis of a generic turbine blade of the first rotor row of a full admission hydrogen turbo pump of a 1 MN thrust class gas generator LOX-LH2 liquid rocket engine (LRE). For this numerical example, the LCF loading turned out to be dominant. Creep turned out to be negligible.

A probabilistic model for quantifying the number of load cycles for nucleation of forging flaws into a crack has been developed. The model correlates low cycle fatigue (LCF) data, ultrasonic testing (UT) indication data, flaw morphology and type with the nucleation process. The nucleation model is based on a probabilistic LCF model applied to finite element analyses (FEA) of flaw geometries. The model includes statistical size and notch effects. In order to calibrate the model, we conducted experiments involving specimens that include forging flaws. The specimens were machined out from heavy duty steel rotor disks for the energy sector. The large disks, including ultrasonic indications on the millimeter scale, were cut into smaller segments in order to efficiently machine specimens including manufacturing related forging flaws. We conducted cyclic loading experiments at a variety of temperatures and high stresses in order to capture realistic engine operating conditions for flaws as they occur in service. This newly developed model can be incorporated into an existing probabilistic fracture mechanics framework and enables a reliable risk quantification allowing to support customer needs for more flexible operational profiles due to the emergence of renewable energy sources. [ABSTRACT FROM AUTHOR]