Plate Material Research Articles

Buckling optimization of variable-stiffness composite plates with two circular holes using discrete Ritz method and potential flow

Potential flow around two equal-radius cylinders is derived analytically and applied to generate the curvilinear fiber path of variable-stiffness composite (VSC) plates with two circular holes. As complex variable theory and conformal mapping are used to generate the potential flow around two equal-radius cylinders, the location and size of the two equal-radius circular holes are arbitrary. By changing the angle of incoming flow, the global fiber angle of a variable-stiffness lamina can be simulated and the local fiber orientation angle at any point is determined by the global potential flow field. Buckling performance of variously-shaped VSC plates with two circular holes are investigated via a novel numerical method − discrete Ritz method (DRM). DRM combines the extended interval integral, Gauss quadrature, and variable stiffness within a rectangular domain and builds a discrete energy system to simulate the plate, which allows the geometric boundaries of the plate to vary. The strain energy of a plate is modeled in the rectangular domain, discretized using Gauss points, and is characterized by variable stiffness, which characterizes both the material distribution and plate geometry simultaneously. After that, a three-dimensional sampling optimization (3DSO) method is adopted to optimize the curvilinear fiber configurations of VSC plates, and its buckling performances are compared with those of constant stiffness composites (CSC) with optimal straight fibers. Significant improvements on load-carrying capacity can be achieved compared to straight ones, demonstrating that using potential flow is one of the most efficient way to generate curvilinear optimal fiber path with maximum load-carrying capacity for VSC plates with material discontinuity. Moreover, DRM exhibits good precision and stability for buckling analysis of VSC plates with complex geometries.

Corrosion failure analysis and solutions of aluminum alloy gas path plate used in sanding device of high-speed train

During the maintenance of a high-speed train, it was frequently found that the anodized aluminum alloy gas path plates in the sanding device had different degrees of corrosion. In this paper, SEM, EDS, XRD and LAD-EDTEST spectrometer were used to analyze the macro and micro morphology, elements and phases of corrosion product, element compositions of the matrix and assembly problem of the gas path plates. The mechanism of delamination spalling corrosion caused by local pitting corrosion of anodized aluminum alloy gas path plate was described. In addition, the properties of the coatings produced by different surface treatment methods and different substrate materials were compared. The test results indicate that the corrosion protection level of the micro-arc oxide coating is higher than that of the anodic oxide coating, which is mainly composed of γ-Al2O3 and contains a certain amount of α-Al2O3. Compared with 2A12-T4 aluminum alloy, the micro arc oxidation (MAO) coating of 6082-T6 aluminum alloy has lower porosity, higher hardness, higher corrosion potential, lower corrosion current, and better corrosion resistance, and 6082-T6 aluminum alloy is more suitable for use as the gas plate material. Meanwhile, it is proposed that the MAO coating with 35 μm can obviously improve the corrosion resistance of the gas path plate.

TSDT vs CPT and FSDT for Free Vibration Analysis of Functionally Graded Incompressible Plates

This article studies vibrational behavior of incompressible functionally graded plates through utilizing classical, first-order shear, and third-order shear deformation plate theories. Plate material properties are presumed to differ continuously in the thickness direction concurringto a power law function. The motion and continuity equations are produced using three different plate theories, and then they are analytically solved for rectangular plates with simple supports utilizingNavier's method. The results are verified by obtaining the plate natural frequency for the power law index value equals zero and comparing them to those reported in previous works. It is shown that transverse vibrational analysis of the classical and first-order shear deformationplate theories for incompressible plates are not as precise as thecompressible ones. It is shown that this issue is due to the fact that according to those theories, unlike the higher order theories, the hydrostatic pressure cannot participate in carrying the bending loads. Consequently, the equivalent flexural stiffness and as a result flexural frequencies decrease. So, to analyze the vibrational behavior of functionally graded incompressibleplates, whether the plate is either thin or thick, higher order theories should be adopted. Also, it is demonstrated that TSDT is the simplest shear deformation plate theory for which the hydrostatic pressure can contribute to withstandig the bending moments. So, it can be a practical theory for free vibration analysis of functionally graded incompressible plates. Finally, this theory has been taken into consideration to analyze the vibrational behavior of rectangular plates made of functionally graded incompressible materials Also detailed parametric studies have been carried out.

Optimizing the Design Structure of Recycled Aluminum Pressing Machine using the Finite Element Method

Optimizing the Design Structure of Recycled Aluminum Pressing Machine using the Finite Element Method

Supplementation of deep neural networks with simplified physics-based features to increase accuracy of plate fundamental frequency predictions

To improve predictive machine learning-based models limited by sparse data, supplemental physics-related features are introduced into a deep neural network (DNN). While some approaches inject physics through differential equations or numerical simulation, improvements are possible using simplified relationships from engineering references. To evaluate this hypothesis, thin rectangular plates were simulated to generate training datasets. With plate dimensions and material properties as input features and fundamental natural frequency as the output, predictive performance of a data-driven DNN-based model is compared with models using supplemental inputs, such as modulus of rigidity. To evaluate model accuracy improvements, these additional features are injected into various DNN layers, and the network is trained with four different dataset sizes. When evaluated against independent data of similar features to the training sets, supplementation provides no statistically-significant prediction error reduction. However, notable accuracy gains occur when independent test data is of material and dimensions different from the original training set. Furthermore, when physics-enhanced data is injected into multiple DNN layers, reductions in mean error from 33.2% to 19.6%, 34.9% to 19.9%, 35.8% to 22.4%, and 43.0% to 28.4% are achieved for dataset sizes of 261, 117, 60, and 30, respectively, demonstrating potential for generalizability using a data supplementation approach. Additionally, when compared with other methods—such as linear regression and support vector machine (SVM) approaches—the physics-enhanced DNN demonstrates an order of magnitude reduction in percentage error for dataset sizes of 261, 117, and 60 and a 30% reduction for a size of 30 when compared with a cubic SVM model independently tested with data divergent from the training and validation set.

Inflammatory tissue response in human soft tissue is caused by a higher particle load near carbon fiber-reinforced PEEK compared to titanium plates

Titanium as the leading implant material in locked plating is challenged by polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK), which became the focus of interest of researchers and manufacturers in recent years. However, data on human tissue response to these new implant materials are rare.Osteosynthesis plates and peri‑implant soft tissue samples of 16 healed proximal humerus fractures were examined (n = 8 CFR-PEEK, n = 8 titanium). Soft tissue was analyzed by immunohistochemistry and µCT. The entrapped foreign bodies were further examined for their material composition by FTIR. To gain insight into their origin and formation mechanism, explanted and new plates were evaluated by SEM, EDX, profilometry and HR-CT.In the peri‑implant soft tissue of the CFR-PEEK plates, an inflammatory tissue reaction was detected. Tissues contained foreign bodies, which could be identified as tantalum wires, carbon fiber fragments and PEEK particles. Titanium particles were also found in the peri‑implant soft tissue of the titanium plates but showed a less intense surrounding tissue inflammation in immunohistochemistry. The surface of explanted CFR-PEEK plates was rougher and showed exposed and broken carbon fibers as well as protruding and deformed tantalum wires, especially in used screw holes, whereas scratches were identified on the titanium plate surfaces.Particles were present in the peri‑implant soft tissue neighboring both implant materials and could be clearly assigned to the plate material. Particles from both plate materials caused detectable tissue inflammation, with more inflammatory cells found in soft tissue over CFR-PEEK plates than over titanium plates. Statement of significanceOsteosynthesis plates are ubiquitously used in various medical specialties for the reconstruction of bone fractures and defects and are therefore indispensable for trauma surgeons, ENT specialists and many others. The leading implant material are metals such as titanium, but recently implants made of polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK) have become increasingly popular. However, little is known about human tissue reaction and particle generation related to these new implant types. To clarify this question, 16 osteosynthesis plates (n = 8 titanium and n = 8 CFR-PEEK) and the overlying soft tissue were analyzed regarding particle occurrence and tissue inflammation. Tissue inflammation is clinically relevant for the development of scar tissue, which is discussed to cause movement restrictions and thus contributes significantly to patient outcome.

Experimental database and analysis of in-plane seismic behaviour of double steel-plate composite walls for wind power tower

A double-steel-plate composite wall (DSCW) is composed of two steel plates, infilled concrete, and connectors. Because of their superior mechanical performance, DSCWs have been widely used in engineering, especially in the field of wind power tower. However, only a few studies have been conducted on the in-plane seismic performance of DSCWs. This study focused on the in-plane seismic performance of DSCWs, and a dataset of the in-plane flexural and shear behaviours of DSCWs including over 200 specimens from more than 30 studies was built. First, various structural configurations and mechanical response parameters were adjusted to the same standard. The same parameters studied by different scholars were extracted and analysed to obtain the general rules of the influence of these parameters on the hysteresis performance of DSCWs (forward analysis), such as the distance-to-thickness ratio, axial load ratio, shear span ratio, connector type, steel plate thickness, material strength, and partition number. Second, a backward analysis using the entire database was conducted on the factors influencing different mechanical response parameters, including the failure modes, yield displacement angle, ultimate displacement angle, ductility, and energy dissipation capacity. Finally, the accuracy of the shear capacity equations in the different codes was verified using shear failure specimens from a database to provide suggestions for engineering practice.

Multiphase flow dynamics in metal foam proton exchange membrane fuel cell

Porous metal foam holds substantial promise as a material for bipolar plates in high-performance proton exchange membrane fuel cells (PEMFC) due to its exceptional properties in reactant redistribution. However, the intricate structure of metal foam flow field (MFF) presents challenges for mass transfer and water management. In this study, a three-dimensional two-phase flow model for metal foam is developed to analyze and capture flow patterns. MFFs are reconstructed based on detailed structural analysis and various pore sizes are discussed. Employing the Volume of Fluid (VOF) method, we delve into multiphase flow dynamics, specifically focusing on the removal of liquid droplets within the MFF. It reveals the MFF with moderate pore sizes exhibit a trade-off performance, striking a balance between optimal mass transfer and minimal parasitic loss. The porous structure's pivotal role is highlighted, contributing significantly to both through-plane and in-plane mass transfer and convection. Furthermore, we classify three flow patterns of liquid droplet, with the “split-up” pattern emerging as the most effective for water management and mass transfer. This study illuminates water behavior in porous metal foam bipolar plates, introduces a systematic methodology for assessing mass transfer and water management capabilities in MFFs for PEMFC.

Secondary neutron dosimetry for conformal FLASH proton therapy.

Cyclotron-based proton therapy systems utilize the highest proton energies to achieve an ultra-high dose rate (UHDR) for FLASH radiotherapy. The deep-penetrating range associated with this high energy can be modulated by inserting a uniform plate of proton-stopping material, known as a range shifter, in the beam path at the nozzle to bring the Bragg peak within the target while ensuring high proton transport efficiency for UHDR. Aluminum has been recently proposed as a range shifter material mainly due to its high compactness and its mechanical properties. A possible drawback lies in the fact that aluminum has a larger cross-sectionof producing secondary neutrons compared to conventional plastic range shifters. Accordingly, an increase in secondary neutron contamination was expected during the delivery of range-modulated FLASH proton therapy, potentially heightening neutron-induced carcinogenic risks to thepatient. We conducted neutron dosimetry using simulations and measurements to evaluate excess dose due to neutron exposure during UHDR proton irradiation with aluminum range shifters compared to plastic rangeshifters. Monte Carlo simulations in TOPAS were performed to investigate the secondary neutron production characteristics with aluminum range shifter during 225MeV single-spot proton irradiation. The computational results were validated against measurements with a pair of ionization chambers in an out-of-field region ( 30cm) and with a Proton Recoil Scintillator-Los Alamos rem meter in a far-out-of-field region (0.5-2.5m). The assessments were repeated with solid water slabs as a surrogate for the conventional range shifter material to evaluate the impact of aluminum on neutron yield. The results were compared with the International Electrotechnical Commission (IEC) standards to evaluate the clinical acceptance of the secondary neutronyield. For a range modulation up to 26cm in water, the maximum simulated and measured values of out-of-field secondary neutron dose equivalent per therapeutic dose with aluminum range shifter were found to be and , respectively, overall higher than the solid water cases (simulation: ; measurement: ). The maximum far out-of-field secondary neutron dose equivalent was found to be ( ) and ( ) for the simulations and rem meter measurements, respectively, also higher than the solid water counterparts (simulation: ( ) ; measurement: ( ) ). We conducted simulations and measurements of secondary neutron production under proton irradiation at FLASH energy with range shifters. We found that the secondary neutron yield increased when using aluminum range shifters compared to conventional materials while remaining well below the non-primary radiation limit constrained by the IECregulations.

Thermalization of Mesh Reinforced Ultra-Thin Al-Coated Plastic Films: A Parametric Study Applied to the Athena X-IFU Instrument.

The X-ray Integral Field Unit (X-IFU) is one of the two focal plane detectors of Athena, a large-class high energy astrophysics space mission approved by ESA in the Cosmic Vision 2015-2025 Science Program. The X-IFU consists of a large array of transition edge sensor micro-calorimeters that operate at ~100 mK inside a sophisticated cryostat. To prevent molecular contamination and to minimize photon shot noise on the sensitive X-IFU cryogenic detector array, a set of thermal filters (THFs) operating at different temperatures are needed. Since contamination already occurs below 300 K, the outer and more exposed THF must be kept at a higher temperature. To meet the low energy effective area requirements, the THFs are to be made of a thin polyimide film (45 nm) coated in aluminum (30 nm) and supported by a metallic mesh. Due to the small thickness and the low thermal conductance of the material, the membranes are prone to developing a radial temperature gradient due to radiative coupling with the environment. Considering the fragility of the membrane and the high reflectivity in IR energy domain, temperature measurements are difficult. In this work, a parametric numerical study is performed to retrieve the radial temperature profile of the larger and outer THF of the Athena X-IFU using a Finite Element Model approach. The effects on the radial temperature profile of different design parameters and boundary conditions are considered: (i) the mesh design and material, (ii) the plating material, (iii) the addition of a thick Y-cross applied over the mesh, (iv) an active heating heat flux injected on the center and (v) a Joule heating of the mesh. The outcomes of this study have guided the choice of the baseline strategy for the heating of the Athena X-IFU THFs, fulfilling the stringent thermal specifications of the instrument.

Efficacy of allogeneic tendon material coracoclavicular ligament reconstruction combined with Kirschner wire and titanium alloy hook plate material fixation in the treatment of acromioclavicular joint dislocation.

To compare the effects of allogeneic tendon coracoclavicular ligament reconstruction combined with Kirschner wire fixation and clavicular hook plate fixation on early postoperative pain, postoperative shoulder joint function score and shoulder joint mobility in patients with acromioclavicular joint dislocation. From January 2020 to January 2023, 43 patients with acromioclavicular joint dislocation admitted to Xi 'an Honghui Hospital were included. Among them, 24 patients were treated with the clavicular hook plate technique (Hook Plate,HP) group, and 19 patients were treated with allogeneic tendon coracoclavicular ligament reconstruction combined with the Kirschner wire technique (Allogeneic Tendon, AT) group. The Constant-Murley score of shoulder joint function 6months after operation, postoperative shoulder joint activity, preoperative and postoperative pain, operation time, intraoperative blood loss and complications were compared between the two groups. All 43 patients were followed up for an average of 9.7 (9-12) months. The intraoperative blood loss in the allogeneic tendon group was less than in the hook plate group. The Constant-Murley shoulder function score was higher than that in the hook plate group 6 months after the operation. The abduction and lifting activity was greater than that in the hook plate group. The visual analogue scale scores at 3days and 14 days after operation were lower than those in the hook plate group. The difference was statistically significant (p < 0.001). There was 1 case (5.3%) of exudation around the Kirschner needle track in the allogeneic tendon reconstruction group, and 5 cases (20.8%) of complications in the hook plate group, including 1 case of internal fixation stimulation, 2 cases of acromion impingement syndrome, 1 case of acromioclavicular joint osteoarthritis, and 1 case of shoulder joint stiffness. The complication rate of the allogeneic tendon group was lower than that of the hook plate group. The clinical efficacy of allogeneic tendon coracoclavicular ligament reconstruction combined with Kirschner wire fixation in treating acromioclavicular joint dislocation (Rockwood type III-V) is better than hook plate internal fixation. The patients have less early postoperative pain and better recovery of shoulder joint function and shoulder joint mobility.

Experimental studies on simultaneously reducing flow drag and noise of a circular cylinder with a downstream porous material plate

Pressure drag and noise level are two key parameters related to flow past a bluff body, thus various active and passive methods have been developed to reduce the drag and noise. The paper presents a passive method of simultaneously reducing the pressure drag and aerodynamic noise associated with flow past a smooth circular cylinder by placing a porous material plate (PMP) downstream the cylinder. Multi-points instantaneous wall pressure and far-field acoustic pressure have been measured in an anechoic wind-tunnel facility. The experimental results confirm that the PMP is effective to reduce both the pressure drag and the noise level, showing an attractive advantage compared with the impermeable splitter plate and porous coating. Parametric studies reveal effects of the pores per inch (PPI) of PMP, PMP-cylinder spacing and incoming flow velocity on the pressure drag and noise level.

Protection performance of aluminum matrix ceramic ball composite materials plate for hypervelocity impact based on FE-SPH adaptive method

Space debris is a major threat to the safety of spacecraft in orbit, and advanced protective materials with lightweight and high impact resistance are effective passive protection solutions. In order to investigate the hypervelocity impact protection performance of aluminum matrix ceramic ball composite materials plate, this paper has carried out the hypervelocity impact test of aluminum matrix ceramic ball composite materials plate, and verified the accuracy of the numerical model based on the FE-SPH adaptive method, and then carried out a comparative study on the hypervelocity impact protection performance of aluminum plate and aluminum matrix ceramic ball composite materials plate with the same area density. The results show that: compared with the aluminum plate conditions, the composite materials plate has a better ability to broken the projectile. Compared with the aluminum plate, the kinetic energy absorbed by the composite materials plate is increased by 37.04%, and the kinetic energy of the generated debris cloud decreased by 69.57%. The proportion of the internal energy dissipation of the composite materials impact system reaches up to 72.03%. The secondary pollution generated by the composite materials plate is less and the hazardous debris have less threat to the rear wall. The research in this paper can provide reference for the selection of hypervelocity impact protection materials.

Jute Fiber Reinforced Biocomposite: Towards Developing Composite Bone Plate

Bone fractures are often treated with metallic bone plates which are inherited some fundamental issues such as stress shielding, bone atrophy, heavyweight, corrosion, and so on. This work aims to develop a jute epoxy composite to investigate its feasibility to use as a composite bone plate. In this work, the natural fiber-based composite made of jute extracted from the jute plant and epoxy resin obtained from LAPOX® METALAM - B is studied experimentally. The mechanical properties such as tensile, compressive, and bending strength of jute/epoxy composite were measured using the universal testing machine (UTM). Moisture absorption test and scanning electron microscope (SEM) image analysis were also performed. The preliminary results suggest that the jute/epoxy composite could be a potential material for a composite bone plate. However, further detailed studies are required to confirm its applicability as a composite bone plate.

DEVELOPMENT OF FRICTION STIR WELDING TOOL FOR HIGH-DENSITY POLY-ETHYLENE (HDPE)–CASE STUDY: FIBERGLASS COMPOSITE MATERIAL

This study aims to develop an effective Friction Stir Welding (FSW) method for composite material of High-Density Poly-Ethylene (HDPE) Pipes. The development of welding tool, there was the addition of an external heating source on the shoulder and probe/pin to overcome the problem of lack of heat resulting from friction between the tool and the material to be welded. The case study was conducted to join the short fiberglass-HDPE composite with a type of ratio of 30% by weight of short fibre and 70% by weight of HDPE, which optimizing parameters such as rotating speed, welding speed, and preheating temperature. The FSW joining process for short fiberglass-HDPE composite sheets was carried out using a Fanuc Series 21i-M CNC milling machine as the driving tool with rotational speed (ω) varied in 3 conditions, namely 600 rpm, 800 rpm and 1000 rpm, and welding speed (v) or feeding at 5 mm/minutes and 10 mm/minutes. The temperature was controlled according to the liquid point of High-Density Poly-Ethylene, which was 130oC, and raised to 150oC and 170oC. The 12 pieces of thermocouple were used along the track on the material and jig plates at the top, middle and bottom. Then, the results of joining the sheets were made in the form of specimens with sizes according to ASTM 3039. The tensile tests of the specimens were carried out at a rate of 0.01 mm/s. The results showed the highest tensile strength was an average value of 24.52 MPa at a rotational speed of 800 rpm, the feeding of 5 mm/min and the temperature of 130oC. The lowest tensile strength was an average value of 17.54 MPa at a temperature of 170°C with a speed of 600 rpm.

CFD modeling of a tubular three-pass solar air heater with phase change material: Investigating heat transfer enhancement and energy efficiency

The present study introduces a novel solar air heater design featuring a tubular surface with three passes arranged in a counter-flow configuration, aimed at improving compactness and enhancing heat transfer characteristics. The research involved the development and validation of a computational fluid dynamics (CFD) model, which was utilized to accurately depict the distribution of solar flux through the system components by comparing the model results with experimental data. The study involved conducting a comparative analysis between the tubular three-pass solar air heater with phase change material (TTPSAH_PCM) and conventional flat plate solar air heaters (FPSAH) to ascertain the superior design characteristics. A thorough investigation was carried out, encompassing evaluations of energy, exergy, outlet temperature, convection heat transfer coefficient, and useful heat gain. The findings indicate that the TTPSAH_PCM outperforms alternative geometries. For instance, when operating at a mass flow rate of 0.006 kg/s, the TTPSAH_PCM demonstrates substantial enhancements in several key metrics, including an 11.4 % increase in the system's daily thermal efficiency, a 17 % improvement in exergy efficiency, and a 4 % rise in outlet air temperature. The convection heat transfer coefficient of TTPSAH_PCM exhibited a 155.6 % increase compared to the FPSAH type. Moreover, the system being investigated demonstrates an 8.5 % rise in useful heat gain. The results underscore the enhanced efficacy of the TTPSAH_PCM system in contrast to alternative solar air heater arrangements, and its applicability for both drying operations and indoor heating applications.

The features of interlayer fracture of composite materials with a variable layup angle under impact loading

Interlayer defects in structural components made of composite materials are caused by the imperfection of the manufacturing process, complex interactions of the constituents, and the effect of impact loads. The presence of these defects decreases the strength of such components and severely affects residual strength. The paper presents a numerical and experimental study of the behavior of a composite material plate with a variable layup angle under impact loading. Impactor velocities before and after multilayer plate perforation, as well as the dimensions of delamination-type defects, are determined experimentally. The Ansys LS-DYNA software in double precision mode is used to simulate the failure of composite plates under impact loading. It has been found that a significant contribution to the decrease in the impact energy is made by the delamination dimensions depending on the layup angle in the stack. The delamination area is related to the residual velocity of the impactor; namely, the larger the delamination area, the greater the decrease in the impactor velocity.

Meat-ing expectations? The influence of plate materials on consumer perceptions of novel mycoprotein

Alternative proteins have gained significant interest as useful adjuncts to facilitate the dietary transition towards more sustainable diets. However, negative consumer perceptions of these products hinder their widespread acceptance and adoption. With emerging research uncovering the role of multisensory factors in consumer perceptions and preferences, manipulating the materials of plates used to serve alternative proteins may help to address these concerns. This within-subject study investigated the influence of a natural material (banana leaf) and a synthetic material (stainless steel) on consumers’ perceptions and preference for mycoprotein. Specifically, perceived product naturalness, healthfulness and tastiness were assessed. Results demonstrated a significant favourable influence of a natural material on consumer perceptions of mycoprotein, compared to a synthetic material (all ps < 0.05). However, differences in preferences were not observed (p =.292). This suggests that other multisensory factors (e.g., product taste and mouthfeel) may play a more important role in consumer preferences for such products. Additionally, having a baseline preference for mycoprotein appeared to moderate the differences in ratings for perceived naturalness of mycoprotein (p <.001). Overall, these findings highlight the role of plate materials in consumer perceptions of mycoprotein and offer valuable insights to potentially develop more effective messaging strategies for these products.

Investigation of the Performance of Hastelloy X as Potential Bipolar Plate Materials in Proton Exchange Membrane Fuel Cells.

The phase, mechanical properties, corrosion resistance, hydrophobicity, and interfacial contact resistance of Hastelloy X were investigated to evaluate its performance in proton exchange membrane fuel cells (PEMFCs). For comparison, the corresponding performance of 304 stainless steel (304SS) was also tested. Hastelloy X exhibited a single-phase face-centered cubic structure with a yield strength of 445.5 MPa and a hardness of 262.7 HV. Both Hastelloy X and 304SS exhibited poor hydrophobicity because the water contact angles were all below 80°. In a simulated PEMFC working environment (0.5 M H2SO4 + 2 ppm HF, 80 °C, H2), Hastelloy X exhibited better corrosion resistance than 304SS. At 140 N·cm-2, the interfacial contact resistance of Hastelloy X can reach as low as 7.4 mΩ·cm2. Considering its overall performance, Hastelloy X has better potential application than 304SS as bipolar plate material in PEMFCs.

High‐Performance Anion Exchange Membrane Fuel Cells Enabled by Nitrogen Configuration Optimization in Graphene‐Coated Nickel for Enhanced Hydrogen Oxidation

Anion exchange membrane fuel cell (AEMFC) technology is attracting intensive attention, due to its great potential by using non‐precious‐metal catalysts (NPMCs) in the cathode and cheap bipolar plate materials in alkaline media. However, in such case, the kinetics of hydrogen oxidation reaction (HOR) in the anode is two orders of magnitude sluggish than that of acidic electrolytes, which is recognized as the grand challenge in this field. Herein, we report the rationally designed Ni nanoparticles encapsulated by N‐doped graphene layers (Ni@NG) using a facile pyrolysis strategy. Based on the density functional theory calculations and electrochemical performance analysis, it is witnessed that the rich Pyridinic‐N within the graphene shell optimizes the binding energy of the intermediates, thus enabling the fundamentally enhanced activity for HOR with robust stability. As a proof of concept, the resultant Ni@NG sample as the anode with a low loading (1.8 mg cm−2) in AEMFCs delivers a high peak power density of 500 mW cm−2, outperforming all of those of NPMC‐based analogs ever reported.