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High-entropy borides (HEBs) are unable to serve in environments above 1800 °C because of their poor oxidation resistance, which severely limits the application of these materials in ultra-high temperature environments. To solve this problem, a series of HEBs with different ratios of metal elements were designed and prepared in this work, and their oxidation behavior above 1800 °C was investigated. The results showed that non-equimolar HEBs possessed excellent oxidation ablation resistance relative to equimolar HEBs. The oxidized surface of (Zr1/4Hf1/4Ta1/4Ti1/4)B2 formed craters due to excessive liquid products and violent volatilization, while (Hf4/5Zr1/15Ta1/15Ti1/15)B2 formed a dense oxide layer after oxidation, which had the best antioxidant performance. The content and type of different metal elements significantly affect the oxidative behavior and products, and the ratio of liquid oxidation products plays a critical role in the antioxidant ability. An appropriate amount of liquid that fills the pores of the solid not only better blocks the diffusion channels of oxygen but also promotes the densification of the oxide layer through flow mass transfer. The oxidation of HEBs to generate corresponding high-entropy oxides avoids thermal mismatch between different oxides, reduces cracks and thermal stresses caused by phase transitions or grain growth, and further promotes the formation of a dense scale. This work provides a first look at the oxidation behaviors of non-equimolar HEBs in an ultra-high-temperature environment and proposes guiding rules for the design of HEB components (limiting the ratio of liquid oxidation products to the range of 10–27 mol%).

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Significant advancements in production technology, materials, component design, and data science foster innovation across industries, including biomanufacturing. Ceramic materials, adapted additive manufacturing processes, and novel construction methods hold immense innovation potential due to ceramics' exceptional thermal, chemical, and mechanical properties. Additive manufacturing enables the creation of intricate ceramic components with unprecedented functionality. Hybridizing manufacturing technologies and materials facilitates direct integration of additional features like sensors and actuators. Despite their potential, ceramic materials remain underutilized. This article aims to spark a discourse on leveraging high-performance ceramic components in biomanufacturing, leveraging superior material properties, innovative design methods, additive manufacturing, process data analysis, and AI. [ABSTRACT FROM AUTHOR]

Rapid urbanization has led to resource shortages, necessitating sustainable approaches in the building industry. This research proposes a preliminary voxel-based modular-architectural design strategy (VMADS), focusing on reusable “H” blocks for component connections and construction. By integrating computational design and robotic fabrication, VMADS enhances precision and efficiency. The framework addresses discrete building theory, prefabrication, and autonomous architecture, emphasizing wood’s anisotropic nature for structural integrity. Experimental results validated VMADS through digital simulations and physical tests, demonstrating its potential to create sustainable, reconfigurable structures and revolutionize construction practices.

Thermal management technology based on loop heat pipes (LHPs) has broad application prospects in heat transfer control for aerospace and new energy vehicles. LHPs offer excellent heat transfer performance, reliability, and flexibility, making them suitable for high-heat flux density, high-power heat dissipation, and complex thermal management scenarios. However, due to limitations in heat source temperature and heat transfer power range, LHP-based thermal management systems still face challenges, especially in thermohydraulic modeling, component design, and optimization. Steady-state models improve computational efficiency and accuracy, while transient models capture dynamic behavior under various conditions, aiding performance evaluation during start-up and non-steady-state scenarios. Designs for single/multi-evaporators, compensation chambers, and wick materials are also reviewed. Single-evaporator designs offer compact and efficient start-up, while multi-evaporator designs handle complex thermal environments with multiple heat sources. Innovations in wick materials, such as porous metals, composites, and 3D printing, enhance capillary driving force and heat transfer performance. A comprehensive summary of working fluid selection criteria is conducted, and the effects of selecting organic, inorganic, and nanofluid working fluids on the performance of LHPs are evaluated. The selection process should consider thermodynamic properties, safety, and environmental friendliness to ensure optimal performance. Additionally, the mechanism and optimization methods of the start-up behavior, temperature oscillation, and non-condensable gas on the operating characteristics of LHPs were summarized. Optimizing vapor/liquid distribution, heat load, and sink temperature enhances start-up efficiency and minimizes temperature overshoot. Improved capillary structures and working fluids reduce temperature oscillations. Addressing non-condensable gases with materials like titanium and thermoelectric coolers ensures long-term stability and reliability. This review comprehensively discusses the development trends and prospects of LHP technology, aiming to guide the design and optimization of LHP. [ABSTRACT FROM AUTHOR]

Eutectic high-entropy alloys (EHEAs) have unique properties, making them a significant sub-branch of HEAs. Researchers are interested in their high strength, good castability, and ductility. However, due to the lack of a complete phase diagram database and previous research results, the traditional trial-and-error method will greatly reduce the research efficiency, and the composition design of EHEAs faces many difficulties. This paper summarizes the recent proposals of the thermo-dynamic factors that have a decisive role in the design of EHEAs. Regarding previous research, we discussed the methods for designing the main eutectic compositions currently used in research. These methods aid in developing novel approaches to fabricating EHEAs. [ABSTRACT FROM AUTHOR]

Additively manufactured mechanical components show great lightweight characteristics and can often be enhanced by integrating biomimetic geometrical features. This study focuses on one specific subcase, namely the substitution of solid cylindrical beams that are under bending with geometrically more complex biomimetic beams. Based on the pseudo-stem of the banana plant as a role model, six geometric beam designs were derived. Given the manufacturing constraints of the PBF-LB/M process, two abstractions were selected for detailed investigation in the main part of this study. The beam lengths were set to 100 mm. Based on parametric optimization simulations, optimal design parameters were identified for the two biomimetic abstractions for 26 different bending load cases ranging from 14 to 350 Nm. Analogous parameter optimizations were performed for a solid cylindrical beam design, which was used as a reference. The results provide detailed design solutions within the investigated intervals for biomimetic beams that can be substituted into more complex mechanical component designs with ease. The analysis provides information on which structures to use for the investigated loads. With the help of the developed numerical models, designers can easily generate biomimetic beam designs for specific bending load values. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

lithium-rich manganese base cathode material (xLi 2 MnO 3-(1-x) LiMO 2 , M = Ni, Co, Mn, etc.) is regarded as one of the finest possibilities for future lithium-ion battery cathode materials due to its high specific capacity, low cost, and environmental friendliness. The cathode material encounters rapid voltage decline, poor rate and during the electrochemical cycling. A series of problems that hinder the commercial application of lithium-rich manganese base cathode material in energy storage area. In view of this, the structural characteristics and discharge performance of lithium-rich manganese base cathode material are discussed in this manuscript as well as the mechanisms governing ion doping, surface coating, morphology, and component design. The reasons behind the performance differences between various doping ions and coating materials acting on Li-rich layered materials are also examined in detail, along with the benefits of double doping and double coating. In order to solve the shortcomings of single ion doping, surface coating, and morphology and component design in the modification of lithium-rich layered materials, a combined modification process based on the aforementioned three alterations is lastly proposed and briefly explained. [ABSTRACT FROM AUTHOR]

Mn-based layered oxides with high theoretical capacity are one of the most promising cathode materials for potassium-ion batteries. However, the Jahn-teller distortion of Mn3+ in Mn-based layered cathodes always brings about harmful disordered structure and irreversible phase transition, resulting in severe degradation of electrochemical performance. Herein, we synthesized P3–K 0.5 Mn 0.6 Ni 0.2 M 0.2 O 2 (M = Fe, Co, FeCo) and systematically investigate the effect of component regulation on the layered structure and electrochemical properties. The P3–K 0.5 Mn 0.6 Ni 0.2 Co 0.2 O 2 exhibits a discharge capacity of 73.77 mAh g−1, demonstrating an excellent capacity retention rate of 70.17 % after 120 cycles at 50 mA g−1. In-depth analysis reveals that P3–K 0.5 Mn 0.6 Ni 0.2 Co 0.2 O 2 possesses a larger K+ layer spacing, making the insertion/extraction of potassium ions become much easier. Furthermore, the introduction of Co into the transition metal layer enhances the content of Mn4+, thereby inhibiting Jahn-Teller distortion and improving structural stability. Especially, the P3–K 0.5 Mn 0.6 Ni 0.2 Co 0.2 O 2 shows a highly reversible single-phase solid solution reaction during the initial cycle, which means the detrimental phase transition of P3–O3 caused by Jahn-Teller effect is effectively suppressed. This work contributes to a better understanding of the effect of component design and regulation on the performance of the layered oxides cathode and provide insight into the design of high-performance cathode materials for potassium-ion batteries. [ABSTRACT FROM AUTHOR]

Metal‐free perovskites are a promising class of materials for X‐ray detection due to their unique structural, optical, and electrical properties. Here, we first delve into the stoichiometry and geometric argument of metal‐free perovskites. Followed, the alternative A/B/X ions and hydrogen‐bonding are clearly introduced to further optimize the materials' stability and properties. Finally, we provide a comprehensive overview of their potential applications for flexible X‐ray images and prospects for metal‐free perovskite development. In conclusion, metal‐free perovskite is a promising material for X‐ray detection. Its stoichiometric and geometric parameters, ion, and hydrogen bond selection, and application prospects are worthy of further study. [ABSTRACT FROM AUTHOR]

In recent years, "high-entropy" materials have attracted great attention in various fields due to their unique design concepts and crystal structures. The definition of high-entropy is also more diverse, gradually expanding from a single phase with an equal molar ratio to a multi-phase with a non-equimolar ratio. This study selected (Na 0.2 Bi 0.2 Ba 0.2 Sr 0.2 Ca 0.2)TiO 3 high entropy ceramics with excellent relaxation behavior. The A-site elements are divided into (x = Na, Bi, Ba) and ((1-3 x)/2 = Sr, Ca) according to their inherent properties. A novel ABO 3 structural energy storage ceramics (NaBaBi) x (SrCa) (1-3 x)/2 TiO 3 (x = 0.19, 0.195, 0.2, 0.205 and 0.21) was successfully fabricated using the high entropy design concept. The ferroelectric and dielectric properties of non-equimolar ratio high-entropy ceramics were studied in detail. It was found that the dielectric constant of ∼4920 and the recoverable energy storage density of 3.86 J/cm3 (at 335 kV/cm) can be achieved simultaneously at x = 0.205. The results indicate that the design concept of high-entropy materials with a non-equal molar ratio is an effective means to achieve distinguished energy storage performance in lead-free ceramics. [ABSTRACT FROM AUTHOR]

• Failure analysis can be utilised for mass reduction of mechanical components. • The failure mode of an engine bracket should not be changed during lightweighting study for safety reasons. • Failure analysis-based mass reduction can lead to a considerable cost improvement. In this study, mass reduction of an engine mounting bracket has been performed without changing the failure mode. Firstly, failure modes were determined experimentally using failure loads provided by the vehicle manufacturer. Then critical stress concentration areas and suitable mass reduction regions were determined by using Finite Element Analysis (FEA) for these load cases. A structural optimisation process was carried out using Design of Experiment-Response Surface Methodology (DOE-RSM) to minimise the mass while keeping the failure load as constant as possible. When the stress values obtained from the preliminary structure are compared with the values obtained from the optimised part, it was seen that this target has been mostly achieved. A total mass reduction of 4.31 % was achieved in the new part through failure mode analysis. Furthermore, it was found that a financial saving of 129,000 Euro could also be achieved. [ABSTRACT FROM AUTHOR]

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Supercapacitors (SCs) are one of the most promising electrical energy storage technologies systems due to their fast storage capability, long cycle stability, high power density, and environmental friendliness. Enormous research has focused on the design of nanomaterials to achieve low cost, highly efficient, and stable electrodes. Ceramic materials provide promising candidates for SCs electrodes. However, the low specific surface area and relatively low surface activity severely hinder the SCs performance of ceramic materials. Therefore, the basic understanding of ceramic materials, the optimization strategy, and the research progress of ceramic electrodes are the key steps to enable good electrical conductivity and excellent electron transport capabilities, and realize economically feasible ceramic electrodes in industry. Herein, we review recent achievements in manufacturing the ceramic electrodes for SCs, including metal oxide ceramics, multi-elemental oxide ceramics, metal hydroxide ceramics, metal sulfide ceramics, carbon-based ceramics, carbide and nitride ceramics, and other special ceramics (MXene). We focus on the unique and key factors in the component and structural design of ceramic electrodes, which correlate them with SCs performance. In addition, the current technical challenges and perspectives of ceramic electrodes for SCs are also discussed.

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Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It has been shown that fatigue damage is brought about by crack initiation and growth and fatigue life can be predicted by crack growth analysis. This study approximated the fatigue life of S45C carbon steel and its change due to the mean stress and loading history effects according to the proposed LDC model (fatigue Life Determined by Cracking model). The equation for the fatigue life approximation was derived assuming the fatigue life was equivalent to the number of cycles for a small crack to grow to a critical size for specimen failure. According to the LDC model, it was shown that the fatigue life and fatigue limit for various mean stresses could be predicted using the effective strain range, which accounted for the crack mouth closure. To confirm the applicability of the LDC model to the loading history effect of carbon steel, the overload fatigue tests were conducted, in which cyclic compressive over strains were applied. Also, non-propagating cracks were observed to investigate the correlation between the fatigue limit and crack arrest phenomenon. It was shown that the fatigue life was reduced by applying the cyclic overloads and the magnitude of the reduction could be predicted using the effective strain range. A procedure was shown to predict reduction of the fatigue life due to mean stress and loading history conservatively. Finally, it was shown that the LDC model was useful to deal with effects of various factors such as mean stress, loading history, specimen size, surface finish and environment in a unified way.

The simplified elastic-plastic correction factor Ke is quoted in fatigue damage assessments for component design to predict elastic-plastic strain from elastic strain without performing elastic-plastic analyses. The Ke factor has been widely used in various design codes, although its value has been determined according to individual policy to achieve conservative assessments. Recently, the American Society of Mechanical Engineers (ASME) modified the Ke factor for thermal loading. By assuming elastic-plastic strain could not become large for thermal loading, a reduced Ke value was applied when the stress was caused by thermal expansion loading. This paper discusses the applicability of Ke for thermal loading to the design code by the Japan Society of Mechanical Engineers (JSME). First, the Ke factor for thermal loading and its background are reviewed, and then, Ke values from several codes are compared. Second, finite element analyses (FEA) for a straight pipe subjected to a fluid temperature transient are conducted to obtain values for comparison of the Ke factor prescribed in the ASME and JSME codes. The Ke values obtained by FEA become larger than those of the revised Ke of the ASME. It is shown that Ke value depends on the boundary condition. The Ke factor of ASME is valid only when the axial displacement is fully constrained or frequency of the fluid temperature fluctuation is fast enough. Third, based on detailed investigations, conservative Ke value for thermal loading is proposed. Finally, the characteristics of the change in the elastic-plastic strain for thermal loading are summarized and discussion is made about how the Ke factor is prescribed in the JSME design code.

High-entropy alloy is a new type of alloy, its excellent physical and chemical properties have attracted extensive attention of the researchers. However, the density of traditional HEAs is high, which greatly limits their engineering applications. In order to reduce the density of HEAs, the low-density elements such as Al, Ti, Mg, Li, and C are used to prepare HEAs, then, a series of LHEAs at equal molar or non-equalmolar concentrations is successfully prepared, showing great application potential in the fields of aerospace, energy and transportation. This paper reviews the research progress of LHEAs. The design guidelines and processing techniques of HEAs are analyzed. The phase structures and properties of LHEAs are introduced according to their system characteristics. The future research direction of LHEAs is prospected.

High-entropy alloy(HEA) coatings with high thermal stability and high temperature resistance of HEA coatings show a new attraction in the field of high temperature coating. The method of preparing HEA coating(HEAc) by laser cladding technology is one of the best preparation methods which can achieve superior performance. The latest research results of HEAc prepared by laser cladding technology were summarized from the view of component design, microstructure, annealing process and properties, high temperature oxidation resistance and other properties. The problems existing in the preparation of HEAc by laser cladding technology were analyzed. It was put forward that the scientific research system should be perfected from the aspects of component design, basic theory, performance law and processing technology in the future. The high-entropy alloy coatings with excellent performance are expected to be prepared.

In modern vehicle development, suspension components have to meet many boundary conditions. In noise, vibration, and harshness (NVH) development these are for example eigenfrequencies and frequency response function (FRF) amplitudes. Component geometry parameters, for example kinematic hard points, often affect multiple of these targets in a non intuitive way. In this article, we present a practical approach to find optimized parameters for a component design, which fulfills an FRF target curve. By morphing an initial component finite element model we create training data for an artificial neural network (ANN) which predicts FRFs from geometry parameter input. Then the ANN serves as a metamodel for an evolutionary algorithm optimizer which identifies fitting geometry parameter sets, meeting an FRF target curve. The methodology enables a component design which considers an FRF as a component target. In multiple simulation examples we demonstrate the capability of identifying component designs modifying specific eigenfrequency or amplitude features of the FRFs. [ABSTRACT FROM AUTHOR]

Narrowband Internet of Things(NB-IoT) is a new communication technology in the field of Internet of Things. It has the characteristics of low power consumption, large capacity, wide coverage and so on. It will be the trend of the development of the Internet of Things. In order to speed up the application of NB-IoT technology, this paper studies the design of temperature and humidity control system based on the application architecture of NB-IoT, gives the communication principle of NB-IoT application architecture, and then uses the component design method to carry out terminal hardware and software design and practices to test the control of temperature and humidity data acquisition system. The test results show that the design of NB-IoT application architecture has good stability and reliability, providing theoretical basis and technical support for the application and development of NB-IoT.

Nowadays, the functional integration of workpieces challenges existing forming processes. The combination of established forming processes – like sheet metal and bulk forming – offers the possibility to counter this issue. The application of bulk forming operations on sheet metal semi-finished products, also called sheet-bulk metal forming (SBMF), is an innovative approach. The potential of SBMF cannot be fully exploited, as there are no recommendations in terms of workpiece design and layout influence on the process result. Therefore, this paper focuses on the analysis of semi-finished products and component design parameters on resulting part and process properties in two extrusion processes in SBMF. The investigation is based on a combined numerical and experimental approach. It is shown that the investigated design parameters, in addition to the achievable dimensional accuracy, substantially influence the occurring tool loads as well as the required process forces. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metal Materials & Engineering is the property of Northwest Institute for Nonferrous Metal Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The optimisation of complex engineering design problems is highly challenging due to the consideration of various design variables. To obtain acceptable near-optimal solutions within reasonable computation time, metaheuristics can be employed for such problems. However, a plethora of novel metaheuristic algorithms are developed and constantly improved and hence it is important to evaluate the applicability of the novel optimisation strategies and compare their performance using real-world engineering design problems. Therefore, in this paper, eight recent population-based metaheuristic optimisation algorithms—African Vultures Optimisation Algorithm (AVOA), Crystal Structure Algorithm (CryStAl), Human-Behaviour Based Optimisation (HBBO), Gradient-Based Optimiser (GBO), Gorilla Troops Optimiser (GTO), Runge–Kutta optimiser (RUN), Social Network Search (SNS) and Sparrow Search Algorithm (SSA)—are applied to five different mechanical component design problems and their performance on such problems are compared. The results show that the SNS algorithm is consistent, robust and provides better quality solutions at a relatively fast computation time for the considered design problems. GTO and GBO also show comparable performance across the considered problems and AVOA is the most efficient in terms of computation time.

Distortion (1), residual stresses and hot cracks can facilitate significant decreases in quality characteristics of casting products. Their reduction by a suitable component design (2) and process control is therefore desirable. In the casting process, these characteristics are assumed as a result of the combination of solidification shrinkage paired with the local self-feeding and the geometric constraints imposed on the component by the mold. In gravity die casting (3) of aluminum (4) with thermally well conducting and rigid metal molds, the control of solidification through a localized adjustment of the heat balance (5) appears to be a suitable approach to minimize these effects. The development of an experimental setup for the assessment of the interdependencies of the alloy, casting geometry and cooling are described in this work. A first series of experiments with A356 aluminum alloy and the introduction to the different methods of evaluation are presented. Furthermore, an approach to improve the understanding of the underlying mechanisms is outlined.

In modern vehicle development, suspension components have to meet many boundary conditions. In noise, vibration, and harshness (NVH) development these are for example eigenfrequencies and frequency response function (FRF) amplitudes. Component geometry parameters, for example kinematic hard points, often affect multiple of these targets in a non intuitive way. In this article, we present a practical approach to find optimized parameters for a component design, which fulfills an FRF target curve. By morphing an initial component finite element model we create training data for an artificial neural network (ANN) which predicts FRFs from geometry parameter input. Then the ANN serves as a metamodel for an evolutionary algorithm optimizer which identifies fitting geometry parameter sets, meeting an FRF target curve. The methodology enables a component design which considers an FRF as a component target. In multiple simulation examples we demonstrate the capability of identifying component designs modifying specific eigenfrequency or amplitude features of the FRFs.

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Aeronautical Materials is the property of Editorial Board of Journal of Aeronautical Materials and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An innovative design procedure has been formulated by developing a mathematical model for the pressure compensator of an axial piston pump. The compensator provides energy saving by making the pump variable displacement type depending on the system load, thereby providing energy saving by better resource management. The procedure involves simple static design steps to ensure a balanced swiveling torque on the swash plate for specified cut-in and cut-off pressure limits. Adopting the basic pump model from the earlier works, the dynamic model of the pump has been updated by including the compensator dynamics. A design sensitivity analysis through dynamic simulation has been performed that corroborates the need of the design through torque balancing. Also, through dynamic simulation, tolerances of some critical dimensions have been identified. The pressure compensator model has been validated against experimental result obtained from a reference pump. [ABSTRACT FROM AUTHOR]

Highlights • The different multiaxial models applied are demonstrated as reasonable candidates. • McD is the most conservative. Findley, FS and BM criteria are the least in order. • Orthogonal shear proves to underestimate the damage compared to the other models. • The influence of the initial ball position proves to exert big influence on damage. • The advances in bearings design could be extended to other industrial components. Abstract A number of structural components, such as those related to wind turbines, are permanently subject to randomly varying load conditions during their service life and are therefore exposed to fatigue failure hazards. For this reason, the use of models for lifetime prediction is indispensable to ensure the structural integrity of at component and the correct operation conditions during its service life. This article compares different multiaxial fatigue criteria, in order to promote a secure and optimal design. Orthogonal shear stress and critical plane models based on stresses (e.g., McDiarmid and Findley), strains (e.g., Brown-Miller) and energy (e.g., Fatemi-Socie and Smith-Watson-Topper) are therefore considered. With this goal, the effect of randomly distributed load histories is analysed using a novel methodology based on the calculation of the stress tensor as a function of time, by interpolating loads with those obtained from response surfaces using Finite Element Method (FEM) models. The critical values of the selected parameters involved in the failure criterion, once estimated, are considered as references and used to determine the fatigue damage based on the Wöhler curves of the material. The methodology proposed allows the most suitable multiaxial fatigue criterion to be recognised by comparing predicted and experimental lab fatigue lives and levels of safety reserve. In this way, a methodology is provided to advance in the optimal test fitting and lifetime prediction of components under real fatigue conditions. [ABSTRACT FROM AUTHOR]

The oxygen compressor is one of the key components in the onboard oxygen generating system (OBOGS), with a high-pressure canister for backup. In this paper, a multistage compressor unit with a non-crank mechanism is proposed for the compression of the generated oxygen for storage in the high-pressure canister in the oxygen backup line of the OBOGS. The working principle, control strategy, and the design method of the key components of the non-crank compressor are provided to realize the preliminary design. The experimental study was carried out to investigate the control accuracy and the technical feasibility, including the compression capacity and the cooling performance. Results show that the motion control program could realize the motion scheme of the compressor with an error of less than 2%. The discharge pressure reached a relative stability after around 40 cycles of compression, while the discharge temperature achieved relative stability after approximately 100 cycles. The average discharge pressure at the last stage could meet the pressure requirement under standard working conditions. The average inlet temperature of the oxygen to the gasholder was 25 °C under standard working conditions.

Manufacturers must assure the reliability of their products, what implies guaranteeing optimal working conditions during their service life. In this work, a methodology is proposed to estimate the damage experienced by a component under non-proportional loading to be made aiming at predicting when the component will fail and where the failure location will happen. In the present case, a novel cyclic counting model is introduced based on a hybrid variant of the rainflow algorithm applied to the results of the Papadopoulos critical plane approach using the Basquin fatigue model. In this way, the damage model is achieved. [ABSTRACT FROM AUTHOR]