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Implementing the generation IV nuclear reactor concept to nuclear service needed elevated temperature component analysis and design methodologies. These components experience elevated temperature loads such as creep, fatigue, creep-fatigue, and ratcheting. Traditional elastic, simplified inelastic, or elastic-perfectly plastic analysis and design methods per Section III, Division 5 fails to capture the detailed material behavior. Full inelastic analysis methods governed by the unified constitutive model (UCM) have shown promise in capturing the complicated material behavior at elevated temperatures. Current Section III, Division 5 design code do not provide guidelines for UCM based full inelastic analysis of Gen. IV components using finite element methods. Gap analysis of the current Section III, Division 5 design code indicated the need to develop unified constitutive models (UCMs) and their optimized parameter sets for performing full inelastic analysis. This paper presents a UCM with two and four nonlinear kinematic hardening rules for diffusion bonded (DB) Alloy 800H. Experiments on DB Alloy 800H are performed for developing and validating a UCM. The developed UCM captures the critical fatigue, creep, and creep-fatigue response features such as hysteresis loop, stress relaxation, rate effects, and cyclic hardening demonstrated by DB Alloy 800H experiments performed. Description of the UCM model developed and its optimized parameters for DB Alloy 800H and cor-responding simulations are presented. Future works to further develop the UCM are discussed.

Degradation found in carbon steel Service Water piping is typically characterized as localized corrosion or “pitting.” Localized corrosion or pitting is identified as small sections of thinning that deviate from the average wall thickness. In its most basic sense, a pit is simply a geometric entity that is abrupt and distinct that can range in size, extent, and density throughout the system. This raises the question of how one defines a pit and what geometric characteristics can be used to create this definition. Research has been conducted to help provide answers to this question through detailed study of wall thickness examination results on operating service water piping in a nuclear power plant. This analysis has determined that the primary geometric characteristics are the depth-to-extent ratio, the extents of thinning, the shape of the pit, and the distance between adjacent pits. Statistical distributions of these characteristics for the evaluated data sets were developed to understand the overall trends of the pitting. With further research, the results of this evaluation can be used to extrapolate these trends of pitting characteristics, with high statistical confidence, to sections of service water piping that have little to no detailed non-destructive examination data. The objective of this paper is to present the preliminary findings of the statistical study on “pitting” and provide a set of geometric characteristics that best define a pit.

This paper provides an overview of the significant revisions to the upcoming 2021 edition of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) Section VIII Division 3, Alternative Rules for Construction of High Pressure Vessels, as well as potential changes to future editions under consideration by the Subgroup on High Pressure Vessels (SG-HPV).

In the past couple of decades there have been significant developments in the fatigue design approach for metallic bellows expansion joints. For example, where there were previously separate fatigue curves for reinforced and unreinforced bellows, there is now only one fatigue curve. This paper describes the developments over time and explains the technical reasons for the changes.

This paper describes development and demonstration of remote crawling systems to support periodic examinations of interim dry storage system (DSS) canisters for spent nuclear fuel in the USA. Specifically, this work relates to robotic crawler developments for “canister” based DSS systems, which form the majority population of DSSs in the USA for interim storage of spent nuclear fuel. Consideration of potential degradation of the welded stainless-steel canister in these systems is required for continued usage in the period of extended operation (PEO) beyond their initial licensed or certified terms. Challenges with performing the periodic examinations are associated with physical access to the canister surface, which is constrained due to narrow annulus spaces between the canister and the overpack, tortuous entry pathways, and high temperatures and radiation doses that can be damaging to materials and electronics. Motivations for performing periodic examinations and developing robotic crawlers for performing those examinations remotely will be presented, and several activities to demonstrate robotic crawlers for different DSS systems are summarized.

The fatigue assessment of safety relevant components is of importance for ageing management with regard to safety and reliability. Those components are subjected to low cycle (LCF), high cycle (HCF), very high cycle fatigue (VHCF) and their combination in terms of complex loading collectives and nonlinear fatigue damage accumulation. Reactor internals, for example, are subjected to thermo-mechanical fatigue induced by operational temperature transients such as stratification loads and to flow induced vibrations. Obviously, methodological gaps within the current fatigue assessment approach, i.e. the assessment of the VHCF behavior, the treatment of the fatigue damage accumulation in combination with the transient endurance limit are to be bridged. Additionally, environmentally assisted fatigue is to be considered properly. Design fatigue curves in international design codes were extended from originally 106 up to 1011 load cycles. Nevertheless, the existing data base for load cycles above ≈ 107 is still insufficient. The cyclic deformation behavior of the material under discussion (AISI 347 within the recent project and AISI 304 within a follow-up project) is different depending on the fatigue regime respectively to the applied load or deformation amplitude. While the LCF behavior is already well investigated and the basic behavior in the HCF regime is fairly well known the VHCF cyclic deformation behavior has not been characterized so far. As a consequence, the real damage accumulation of variable amplitude combinations consisting of LCF- and HCF/VHCF loads is still widely unknown. A cooperative R&D project of MPA Stuttgart, WKK University of Kaiserslautern and Framatome GmbH addresses the existing gaps of knowledge discussed above and has recently been finished. The following topics will be discussed in detail in the paper: • Basic characterization of the HCF and VHCF behavior at relevant operational temperatures in air at 106 – 2·109 load cycles (base material and welded material) • Fatigue behavior at variable amplitude loading (combination of LCF / HCF and LCF / VHCF) • Numerical simulations and fatigue assessment of VHCF-regime loadings • Development of a fatigue assessment methodology under consideration of the transient endurance limit and damage accumulation effects including assessment and adaptation of appropriate fatigue damage parameters

The safety and reliability of all systems has to be maintained throughout the lifetime of a nuclear power plant (NPP). This requires a systematic ageing management procedure for justifying their safe long term operation. One fundamental part in this process is to demonstrate the integrity of the nuclear power plant components. The European project ATLAS+ aims to develop and validate advanced methods of structural integrity assessment applicable in the ageing and lifetime management of primary circuit components. To support development and validation of those methods a large scale test programme was developed with the aim to investigate fracture behavior of relevant piping material at the component level. Three of the planned large scale experiments focus on the fracture behavior of flawed ferritic pipe segments made of material WB 36 (15 NiCuMoNb 5); this material is representative of secondary feedwater lines installed in German NPPs. In order to improve understanding of test results post-test simulations and fractographic examination of all large scale tests are planned, some of them have been already performed. In this paper the post-test simulation of the mock-up FP2 (ferritic pipe with outer semi-elliptical circumferential crack) is presented and discussed. This mock-up was selected because it experienced an unexpected brittle fracture during the test, which occurred after limited ductile crack propagation. To investigate both the ductile and the brittle crack propagation phases of the test detailed ductile tearing analysis and brittle fracture assessment have been performed. In addition, relevant results of fractographic examination of the mock-up FP2 are presented and discussed.

Pressure-temperature ratings for aluminum alloy flanges made from ASTM B247 3003-H112 and 6061-T6 materials are covered in ASME B31.3 Appendix L since 1995. They were previously included in ANSI B16.5 between 1960 and 1968, and in ANSI B16.31 Non-ferrous Alloy Flanges from 1968 and until it was withdrawn in 1981. In 2018, Xu and Rana [PVP 2018-84076] used a modified version of the rules for establishing the pressure-temperature rating from ASME B16.5 Steel Flanges to re-assess the pressure-temperature rating of aluminum alloy currently listed in ASME B31.3 Appendix L. Based on their work, they recommended raising the pressure-temperature ratings for Classes 150, 300 and 600, as well as expanding rating to cover Classes 900 and 1500. In this paper, the author will revisit this topic, explain the background of why ANSI B16.31 was withdrawn and the drawbacks of higher pressure-temperature rating of aluminum alloy flanges. The author will also explain the concept of “ceiling pressure” used in B16 standards to cap the maximum pressure rating for flanges and valves, and significant difference in the modulus of elasticity between Carbon Steel and Aluminum alloys, and its impact on flange rigidity and leak tightness, and will propose alternative rules for establishing the pressure-temperature ratings for aluminum alloy flanges.

A three-dimensional, freeze-bonded, Discrete Element Method (DEM) numerical model has been developed to simulate various ice rubble/ridge interaction scenarios. The numerical model was validated against the physical tests conducted by C-CORE under the Pipeline Ice Risk Assessment and Mitigation (PIRAM) Joint Industry Project. Accurate representation of ice block geometries and sizes distributions was achieved using clumped particles, rather than the traditional DEM spheres. With the use of clumped ice blocks the numerical model was able to characterize the initial keel conditions (macro porosity and freeze bond contacts) and capture interlocking behavior between ice blocks. A DEM gravel seabed model was then introduced to the clumped ice block model to allow for better representation of soil response during the simulated experiments. The main features of these model developments are described in this paper, along with a comparison of simulated results and large scale physical test results. From this work it was concluded that: (1) clumped ice blocks give more representative ice block shapes for an ice keel than spherical ice blocks, which better capture ice block interactions and overall ridge keel properties and behavior; and (2) a DEM model of the seabed gravel provided a better representation of the seabed than was possible with a continuous stiffness plane, which had important implications for modelling the keel-seabed interactions. The development and inclusion of these two new model features were found to significantly improve the accuracy of the DEM model in reproducing physical test results, while still being sufficiently computationally efficient as to allow for simulation of interactions full-scale ice ridges.

In recent past, there have been unforeseen sour service pipeline failures in the oil and gas industry. Sub-optimal microstructure resulting in high hardness (above 250 HV10) in pipeline steel is one of the root causes of such failures. Poor girth weld quality is another leading cause which adversely affects pipeline integrity and safe operations in sour environments. While advancements in welding technologies have led to consistency in production girth welds, effects of welding parameters on performance of carbon steel pipeline girth welds for sour service are not well understood. So, a systematic study is needed to understand the effects of various welding parameters on weld properties and performance. This paper aims at evaluating the effects of various welding parameters on performance of girth welds to provide welding practice guidelines for sour service pipeline applications. In this effort, several welds on X65 grade line pipe girth welds using commercially available welding consumables were made to study the effects of preheat, hot pass tempering, copper backing, root pass heat input, wire consumable chemistry, single vs. dual torch, metal transfer mode, pipe fit-up (root gap, misalignment), on weld root performance. Detailed microhardness mapping and microstructural characterization were conducted. It was evident that the welding parameters studied have a significant impact on root performance. While preheat and pipe fit-up showed most significant impact on weld root performance, other parameters also affected the root performance by varying degree. Based on these results, recommendations for industry are provided to improve reliability of pipeline girth welds in sour service application.

Reducing fuel consumption has been a driving factor for researchers and manufacturers to continually develop improved methods for reducing the weight of automobiles or lightweighting. These vehicle lightweighting demands have directed researchers to look to using materials that are typically more difficult to manufacture in their studies. As a result, friction stir processing techniques are being looked at more closely. There are advantages to using friction stir methods. Dissimilar metals can be welded and fine-grained products can be created using friction stir methods to name a few. It can be an ideal solution for manufacturing high-conductive metals and alloys. Foamed aluminum tube similar to the one shown by Yoshiko Hangai et al [1] can be formed using the proposed process which could be used to develop lightweight automobile components. This paper provides preliminary results and insights gained when fine metal powders were used in a friction stir back extrusion (FSBE) setup. The tooling consisted of a D2 tool steel die with an H13 rotating probe mounted in a CNC mill. Within the die, commercially pure aluminum powder was topped by an aluminum cap with a milled pocket in the center. This pocket was used to locate the spin tool in the center of the cap and reduce the potential for the tool to drift and deflect. The cap was also used for compacting the powdered aluminum. X-ray diffraction indicated that Al13Fe4 was formed, indicating that the temperature within the die reached a minimum of 800°C and also indicated that the powder had the potential to partially sinter and melt.

In this paper, mechatronic design of a novel robotic shark for coral reef detection is presented. To obtain good maneuverability, a barycenter regulating device is designed to assist the posture adjustment of the robotic shark at low speed. Based on STAR-CCM+ software, the lift coefficients and drag coefficients of pectoral fin are calculated using overlapping grid technique. Based on Newton-Euler approach, a dynamic model with particular consideration of pectoral fins for three-dimensional motion is established. A CPG controller is used to generate rhythmic motion of each joint. Furthermore, based on the dynamic model, three-dimensional trajectory of spiral motion and swimming speed in different oscillation parameters are simulated. The results show that swimming speed of the robotic shark can be improved by increasing the amplitude and frequency or decreasing the phase difference. Also, oscillation frequency plays a more significant role. Furthermore, under the action of single pectoral fin, the robotic shark can achieve spiral motion and the turning radius is about 35.8m under the parameters set in this article.

Mechanical recovery techniques are used to clean up oil spills in marine environments; however, their efficiency is challenged when dealing with heavy oil, ice covered water and high sea states. Current mechanical recovery techniques are based on removing oil from the water surface, however, a significant amount of oil could remain in the water column below the surface due to turbulent ocean conditions, the density of heavy oil and oil escaping underneath the booms when the sweeping speed increases. To enhance the oil recovery effectiveness, oil particles in the water column need to be guided to the surface to be recovered by the skimmers. This paper focusses on the development of a test protocol and physical testing in C-CORE’s lab of a bubbler system for enhancing the harsh environment oil spill recovery. Air bubbles produce an upward flow in the water body, which guides the submerged particles to the surface. The air bubbles also attach to the oil particles, leading to an increase in the buoyancy and rate at which oil droplets rise to the surface. By adopting this technique for oil recovery, additional oil particles can be brought to the surface. In the study, the bubbler system was tested in both stationary and advancing conditions with medium and heavy oils. The results of the stationary and advancing tests indicate that the oil recovery ratios can be significantly enhanced by using an optimized bubbler system. Different types and configurations of bubblers were tested by varying the airflow rates and bubbler advancing speeds to determine the optimal solution. The optimal bubbler system has been observed to enhance the recovery ratio from 41.5% to 84.8% with airflow rates ranging from 0.05 to 0.20 CFM/foot. Furthermore, the effective integration of the bubbler system with a mechanical recovery system, its deployment and retrieval in a near field condition were demonstrated during tests in an outdoor tank.

This paper describes the current implementations and development trends of condition monitoring as it pertains to ship propulsion systems. In terms of total incidents in the shipping industry in the last five years, failures relating to the propulsion system represent the majority. Condition monitoring offers effective early detection of failure which translates to increased reliability and decreased maintenance costs. Current industrial practices are often limited to performance monitoring rather than condition monitoring. Special focus is afforded to how condition monitoring is implemented on board ships, which regulatory codes are relevant and the summary of state-of-the-art research in marine machinery. Moreover, operation and monitoring in extreme environmental conditions, such as the Arctic and Antarctic with ice impact on the propulsion has been discussed. The new developments, in particular, digital twin approaches in health and condition monitoring have been highlighted, considering its pros and cons and potential challenges.

Additive manufacturing process of maraging steel has been studied for high value parts in aerospace and automotive industries. The hybrid additive / subtractive manufacturing is effective to achieve tight tolerances and surface finishes. The additive process induces anisotropic mechanical properties of maraging steel, which depends on the laser scanning direction. Because anisotropy in the workpiece material has an influence on the cutting process, the surface finish and the dimension accuracy change according to the direction of the cutter feed with respect to the laser scanning direction. Therefore, the cutting parameters should be determined to control the cutting force considering material anisotropy. The paper discusses the cutting force in milling of maraging steel stacked with selective laser melting, as an additive manufacturing process. Anisotropic effect on the cutting forces is proved with the changing rate of the cutting force in milling of the workpieces stacked by repeating laser scanning at 0/90 degrees and 45/−45 degrees. The cutting forces, then, are analyzed in the chip flow models with piling up of orthogonal cuttings. The force model associates anisotropy with the shear stress on the shear plane. The changes in the cutting forces with the feed direction are discussed in the cutting tests and analysis.

There is increasing demand for subsea transport of well-produced fluids through corrosion resistant pipelines such as stainless steel or bimetallic pipes. The latter are made of carbon steel (CS) pipe and a thin (typically 3.0 mm thick) internal layer of corrosion resistant alloy (CRA) such as 316L, 625, 825 or 904L. The CRA and CS layers are adhered either metallurgically or mechanically by a means of an interference fit. Although less mature than other products, mechanically lined pipes (MLP) are more readily available and economical than both stainless steel or hot-roll bonded (HRB) metallurgically clad pipes. One of the gaps that remains to be filled relates to a reliable assessment method for confirming the MLP integrity during offshore installation and subsea service. The CRA liner in MLP is metallurgically bonded to CS at pipe ends by overlay welding, typically deposited using alloy 625 consumable. At the triple-point interface between the liner, overlay and host pipe, cracks may initiate from fabrication flaws and grow during installation or in service. Therefore, the engineering critical assessment (ECA) should be carried out to evaluate the risk of triple-point cracks breaching the CRA layer at any stage of the pipeline’s life cycle. Currently, no recognised ECA approach exists to allow completing such an assessment. Therefore, a bespoke integrity assessment procedure has been developed and validated both numerically and via laboratory testing. This paper outlines the ECA procedure for triple-point flaws in subsea MLP pipelines, which is undertaken through a combined analytical and numerical calculation and small-scale fracture testing. Fatigue crack growth due to cyclic loading is estimated using a geometry-specific stress intensity factor (SIF) solution derived by finite-element analysis (FEA). Ductile tearing during fracture load events is quantified by small-scale fracture testing on specimens with a representative geometry, designed to match the crack tip constraint of triple-point cracks in MLP.

The oil and gas industry faces many challenges as it is committed to provide energy to a world in transition. Declining prices impose constraints to new developments, either greenfield or brownfield. Additionally, the industry’s commitment to long-term value creation with reduced carbon footprint is confronted with the traditional solutions for well construction, production and processing, which consume significant amount of energy with corresponding high CO2 emissions. In this scenario, subsea production and processing technology has been a key enabler for the exploitation of oil and gas resources. This paper presents a holistic review of trends in subsea technology development over recent years which have direct impact on the heart of the subsea production system, namely the subsea tree. The technological developments considered are in different subsea applications such as robotic automation, communication systems, and all-electric systems. The objective of the ongoing research is to perform structural and fundamental analysis of subsea production and injection systems and address the question on how technological developments can be utilized to design an overall better subsea production system so the industry may fully benefit from the economic and ecological impact brought by the joint use of these technologies. Opportunities for reevaluating barrier philosophy to identify technical and economic opportunities for design simplifications of subsea trees that still leave enough pressure barriers in all operational modes are also considered. The analyses presented indicate the current stage of the examined technologies and their potential at reducing both capital and operational cost of subsea systems. These results will be the basis for the future evaluation of improved and new design solutions within the scope of the ongoing project performed by the Norwegian University of Science and Technology and its industrial partners.

Gas turbine is widely used in aviation and energy industries. Gas path fault diagnosis is an important task for gas turbine operation and maintenance. With the development of information technology, especially deep learning methods, data-driven approaches for gas path diagnosis are developing rapidly in recent years. However, the mechanism of most data-driven models are difficult to explain, resulting in lacking of the credibility of the data-driven methods. In this paper, a novel explainable data-driven model for gas path fault diagnosis based on Convolutional Neural Network (CNN) using Local Interpretable Model-agnostic Explanations (LIME) method is proposed. The input matrix of CNN model is established by considering the mechanism information of gas turbine fault modes and their effects. The relationship between the measurement parameters and fault modes are considered to arrange the relative position in the input matrix. The key parameters which contributes to fault recognition can be achieved by LIME method, and the mechanism information is used to verify the fault diagnostic proceeding and improve the measurement sensor matrix arrangement. A double shaft gas turbine model is used to generate healthy and fault data including 12 typical faults to test the model. The accuracy and interpretability between the CNN diagnosis model built with prior mechanism knowledge and built by parameter correlation matrix are compared, whose accuracy are 96.34% and 89.46% respectively. The result indicates that CNN diagnosis model built with prior mechanism knowledge shows better accuracy and interpretability. This method can express the relevance of the failure mode and its high-correlation measurement parameters in the model, which can greatly improve the interpretability and application value.

This paper reports a new turbine research facility that was recently completed in Japan Aerospace Exploration Agency (JAXA). The facility is a full annular rotating transonic turbine rig that allows a continuous operation of scaled and/or full-scale axial HPT or LPT. The rig design was especially focused on the ability of simulating the aerodynamic and thermal interaction between main gas paths and various / massive secondary air flows at conditions of dominant aero-heat parameters well matched to those of modern aero-engines. Cooling air can be delivered to the airfoils of vanes/blades and the endwalls separately at a massflow range covering the typical conditions. Rotor forward and aft purge air as well as through-casing cooling air can be injected with each flowrate independently controlled. The facility, which has significant capabilities with several large compressors of 10MW in total, 5MW mainflow heater, 6MW drive motor/generator, etc., can be applied to a very wide range of turbine designs. A series of shakedown testing has been carried out since the completion of construction in 2019. The commissioning phase of the rig will complete in early 2021 and then the rig will enter service. The very first test with a scaled HPT is planned to start in the last quarter of 2021.

Buoyancy-induced flow occurs inside the rotating compressor cavities of gas turbines. These cavities are usually open at the inner radius, but in some industrial gas turbines, they are effectively closed. This paper presents measurements of the disc heat transfer and rotating flow structures in a closed cavity over a wide range of engine relevant conditions. These experimentally derived distributions of disc temperature and heat flux are the first of their kind to be published. The radial distribution of the non-dimensional disc temperature virtually collapsed onto a single curve over the full experimental range. There was a small, monotonic departure from this common curve with increasing Reynolds number; this was attributed to compressibility effects where the core temperature increases as the rotational speed increases. These results imply that, if compressibility effects are negligible, all rotating closed cavities should have a disc temperature distribution uniquely related to the geometry and disc material; this is of important practical use to the engine designer. Unsteady pressure sensors detected either three or four vortex pairs across the experimental range. The number of pairs changed with Grashof number, and the structures slipped relative to the rotating discs by less than 1% of the disc speed.

Most collaborations between academia and industry involve industry funded and defined research projects. There are, however, many more opportunities for activities that lead to a stronger partnership that benefits both. Moving from individual projects to a wider collaboration aligned along industry needs and academic strengths, to form academic centers of excellence provides a more involved collaboration. This paper provides an example of how companies can become more than a research partner but, instead, can get involved in the curriculum and educational efforts of the academic partner.

The evolution of industrial gas turbines towards increased efficiency and performance requires even higher operating temperatures for the engines. In order to remain competitive in the market, OEM companies continuously need to develop maintenance programs and repair technologies able to extend the life of these components as much as possible. The repair technology improvement is fundamental to reduce scrap rates and maintenance costs to be competitive on the market. The Ansaldo Repair Centre answers to this market demand by providing advanced and competitive repair techniques and an increasing broad repair portfolio to its customers. This paper describes the steps and approach to determine the repair process of GT26 LPT Blade 1 in order to allow the component to run another service interval. The base material status and the indication found after service was used as the foundation for a development of a dedicated repair sequence from stripping, to suitable heat treatments, to enhanced repair technique to recoating of the blade. Particular attention was paid to the most damaged area, for which a particular welding procedure including an optimized filler material has been applied for the rebuilding of the tip and platform zones as well as for the restoration of the unique tip closing features.

The paper presents the results of aeromechanical design of a large-scale model stage for a high-efficient low-noise fan designed for an advanced civil geared turbofan engines with ultra-low rotational speeds of rotor blades (313.4 m/s), high flow specific capacity (up to 202 kg/m2/s) and high bypass ratio (13.5). Total pressure ratio in the bypass duct of the fan model stage is 1.38. To ensure the experimental studies, characteristics are calculated from choking to a surge line within a wide range of rotational speeds. For the studies of the experimental fan model (EFM), a design project is developed and used in manufacturing a fan stage with 0.7-m rotor diameter for tests at the C-3A acoustic test facility. The manufacturing technology for blades made of polymer composite materials (PCM) is of particular importance. Rotor blades of the geared fan model are made of PCM. The analysis of experimental data and their comparison with the computation results within the range of corrected rotational speeds from 0.325 to 1.0 are presented. At first, only gas-dynamic and strength characteristics of the stage are studied. The analysis shows a good agreement of calculated integral parameters with the experimental data. Acoustic performances of the EFM will be studied later on.

U.S. Navy marine gas turbine engines serve as primarye and auxiliary power sources for several current classes of ships. Early observations noted in the 1960s and 1970s revealed severe corrosion attack on the first stage blade and vane components of a shipboard marine gas turbine engine that caused engine failure after only several hundred hours. In gas turbine development, there is always a drive and need to enhance the performance and life of engines. The virtues of using Ni-base superalloys in hot-section components has been well recognized and practiced as a means of substantial increase in turbine-inlet temperature, resulting in improvements in thermal efficiency, durability, and performance of engines. The USN shipboard environment (the marine environment) is high in salt laden air and water, coupled with air and fuel sulfur species that cause aggressive corrosion in gas turbine hot sections. Materials that can function in this environment are considered to be “Marinized”. Higher engine power density and pressure ratios for new engine designs will increase maximum blade, vane, and rotor metal temperatures from a mainly Low Temperature Hot Corrosion (LTHC) regime into both the High Temperature Hot Corrosion (HTHC) and Oxidation Corrosion regions. It is expected that future increased surface combatant loads and operational changes will require increased gas turbine operating temperatures and change the associated operating environment to one where Type I and Type II hot corrosion AND oxidation will be prevalent in newly anticipated operational profiles. The advanced gas turbine upgrade package will include better corrosion and oxidation resistant capability and/or higher temperature capable materials and their associated component overhaul methodologies. New materials need to be created and developed for use in more aggressive environments and higher temperature operations. The main cause of the shorter time between overhauls is the materials deterioration of the engine components associated with the hot section of the engine, e.g. turbine airfoils. The deterioration mechanisms are hot corrosion, with Type 1 hot corrosion mechanism becoming operative at the higher temperatures. The goal of this paper is to evaluate methods to enable running the engine at high power while getting back to the longer mean time between overhauls. The method to achieve the longer time is to evaluate and propose for implementation materials, which can withstand the higher temperatures and at the same time mitigate the operative corrosion mechanisms associated with marine environments.