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Wear and Corrosion Resistance of Al0.5CoCrCuFeNi High-Entropy Alloy Coating Deposited on AZ91D Magnesium Alloy by Laser Cladding
摘要： In order to improve the wear and corrosion resistance of an AZ91D magnesium alloy substrate, an Al0.5CoCrCuFeNi high-entropy alloy coating was successfully prepared on an AZ91D magnesium alloy surface by laser cladding using mixed elemental powders. Optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction were used to characterize the microstructure of the coating. The wear resistance and corrosion resistance of the coating were evaluated by dry sliding wear and potentiodynamic polarization curve test methods, respectively. The results show that the coating was composed of a simple FCC solid solution phase with a microhardness about 3.7 times higher than that of the AZ91D matrix and even higher than that of the same high-entropy alloy prepared by an arc melting method. The coating had better wear resistance than the AZ91D matrix, and the wear rate was about 2.5 times lower than that of the AZ91D matrix. Moreover, the main wear mechanisms of the coating and the AZ91D matrix were different. The former was abrasive wear and the latter was adhesive wear. The corrosion resistance of the coating was also better than that of the AZ91D matrix because the corrosion potential of the former was more positive and the corrosion current was smaller.
关键词： laser cladding,wear,AZ91D magnesium alloy,high-entropy alloy coating,corrosion
更新于2025-11-21 11:24:58
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A study of metallurgy and erosion in laser surface alloying of AlxCu0.5FeNiTi high entropy alloy
摘要： AlxCu0.5FeNiTi high entropy alloy coating is synthesized by premixed high purity Cu, Fe, Ni and Ti powders on AA1050 aluminium substrate by laser surface alloying, with the aim to improve microhardness and erosion rate. Phase constituents, microstructure and microhardness were investigated using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Vickers Microhardness tester, respectively. The erosion behavior of AlxCu0.5FeNiTi coating is checked using an air jet erosion setup. SEM images show presence of three regions. Percentage compositions of these regions are evaluated using Energy Dispersive Spectroscopy. XRD analysis of AlxCu0.5FeNiTi coating confirmed that these regions are a mixture of disordered BCC and two FCC solid solution phases. The microhardness of the AlxCu0.5FeNiTi HEA is 18 times that of the AA1050 aluminium substrate. Results show that AlxCu0.5FeNiTi HEA coating has improved erosion resistance.
关键词： Laser Surface Alloying,Microhardness,Microstructure,High Entropy Alloy,Erosion rate
更新于2025-11-21 11:18:25
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Rapid Alloy Development of Extremely High-Alloyed Metals Using Powder Blends in Laser Powder Bed Fusion
摘要： The design of new alloys by and for metal additive manufacturing (AM) is an emerging field of research. Currently, pre-alloyed powders are used in metal AM, which are expensive and inflexible in terms of varying chemical composition. The present study describes the adaption of rapid alloy development in laser powder bed fusion (LPBF) by using elemental powder blends. This enables an agile and resource-efficient approach to designing and screening new alloys through fast generation of alloys with varying chemical compositions. This method was evaluated on the new and chemically complex materials group of multi-principal element alloys (MPEAs), also known as high-entropy alloys (HEAs). MPEAs constitute ideal candidates for the introduced methodology due to the large space for possible alloys. First, process parameters for LPBF with powder blends containing at least five different elemental powders were developed. Secondly, the influence of processing parameters and the resulting energy density input on the homogeneity of the manufactured parts were investigated. Microstructural characterization was carried out by optical microscopy, electron backscatter diffraction (EBSD), and energy-dispersive X-ray spectroscopy (EDS), while mechanical properties were evaluated using tensile testing. Finally, the applicability of powder blends in LPBF was demonstrated through the manufacture of geometrically complex lattice structures with energy absorption functionality.
关键词： multi-principal element alloys,high-entropy alloys,additive manufacturing,rapid alloy development,powder blends,laser powder bed fusion
更新于2025-11-21 11:01:37
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Precipitation behavior of selective laser melted FeCoCrNiC0.05 high entropy alloy
摘要： Interstitial elements are e?ective to strengthen high entropy alloys (HEAs). In this work, FeCoCrNiC0.05 was prepared by selective laser melting (SLM) followed by annealing. The e?ects of annealing on the microstructures and mechanical properties of the SLMed FeCoCrNiC0.05 were investigated. Results show that, nano-scale Cr23C6-type carbides can precipitate under annealing conditions, leading to higher yielding strength. The SLMed FeCoCrNiC0.05 annealed at 1073 K for 0.5 h has a yielding strength of 787 MPa and an elongation of 10.3%. Precipitation kinetics in SLMed FeCoCrNiC0.05 has been established according to Avrami formula. The high strength can be attributed to solid solution hardening, precipitation hardening and cell-like structures.
关键词： Precipitation kinetics,Hardening mechanism,Selective laser melting,Mechanical properties,High entropy alloy
更新于2025-11-14 17:04:02
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Entanglement measures of a new type pseudo-pure state in accelerated frames
摘要： In this work we analyze the characteristics of quantum entanglement of the Dirac field in noninertial reference frames in the context of a new type pseudo-pure state, which is composed of the Bell states. This will help us to understand the relationship between the relativity and quantum information theory. Some states will be changed from entangled states into separable ones around the critical value F = 1/4, but there is no such a critical value for the variable y related to acceleration a. We find that the negativity NABI ((cid:26)TA ABI ) increases with F but decreases with the variable y, while the variation of the negativity NBI BII ((cid:26)TBI BI BII ) is opposite to that of the negativity NABI ((cid:26)TA ABI ). We also study the von Neumann entropies S((cid:26)ABI ) and S((cid:26)BI BII ). We find that the S((cid:26)ABI ) increases with variable y but S((cid:26)BI BII ) is independent of it. However, both S((cid:26)ABI ) and S((cid:26)BI BII ) first decreases with F and then increases with it. The concurrences C((cid:26)ABI ) and C((cid:26)BI BII ) are also discussed. We find that the former decreases with y while the latter increases with y but both of them first increase with F and then decrease with it.
关键词： pseudo-pure state,concurrence,negativity,noninertial frame,entanglement,von Neumann entropy
更新于2025-09-23 15:23:52
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Driver’s eye-based gaze tracking system by one-point calibration
摘要： The accuracies of driver’s gaze detection by previous researches are affected by the various sitting positions and heights of drivers in case that initial calibration of driver is not performed. By using dual cameras, the driver’s calibration can be omitted, but processing time with complexity is increased. In addition, the problem of disappearing corneal specular reflection (SR) in the eye image as the driver severely turns his/her head has not been dealt in previous researches. To consider these issues, we propose a gaze tracking method based on driver’s one-point calibration using both corneal SR and medial canthus (MC) based on maximum entropy criterion. An experiment with collected data from 26 subjects (wearing nothing, glasses, sunglasses, hat, or taking various hand pose) in a vehicle, showed that the accuracy of the proposed method is higher than that of other gaze tracking methods. In addition, we showed the effectiveness of our method in the real driving environment.
关键词： Maximum entropy criterion,Pupil,Initial calibration of driver,Driver’s gaze detection,corneal specular reflection and medial canthus,NIR camera and NIR illuminator
更新于2025-09-23 15:23:52
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Double-exponential kinetics of binding and redistribution of the fluorescent dyes in cell membranes witness for the existence of lipid microdomains
摘要： New technique of detecting lateral heterogeneity of the plasma membrane of living cells by means of membrane-binding fluorescent dyes is proposed. The kinetics of dye incorporation into the membrane or its lateral diffusion inside the membrane is measured and decomposed into exponential components by means of the Maximum Entropy Method. Two distinct exponential components are obtained consistently in all cases for several fluorescent dyes, two different cell lines and in different types of experiments including spectroscopy, flow cytometry and fluorescence recovery after photobleaching. These components are attributed to the liquid-ordered and disordered phases in the plasma membrane of studied cells in their dynamic equilibrium.
关键词： Kinetics,Maximum Entropy Method,Decomposition,Lipid phases,Plasma membrane heterogeneity
更新于2025-09-23 15:23:52
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Assessment of concentrated solar power (CSP) technologies based on a modified intuitionistic fuzzy topsis and trigonometric entropy weights
摘要： Concentrated solar power (CSP) technology has shown considerable long-term growth with varying levels of peak development and stall phases over the years. More and more countries are finding CSP technology attractive for the production of electricity and other applications. CSP offers a variety of applications where solar power can be used appropriately, although the debate about which CSP technology has a better future perspective is still ongoing. This technology sector has seen a multitude of advancements and technological innovations. These improvements are primarily concerned with the design of the collectors and the related materials they are made from, the heat transfer processes, and the production and accumulation of energy. In order to assess these CSP technologies, in this paper we propose a fuzzy multi-criteria method. Then, Solar tower (ST), Parabolic solar trough (PST), Compact linear Fresnel reflector (CLFR), and Dish Stirling (DS) are evaluated using a modified intuitionistic fuzzy TOPSIS with a trigonometric entropy vector weight.
关键词： Sustainability,Concentrated solar power (CSP),Trigonometric entropy,Technological assessment,Intuitionistic fuzzy TOPSIS
更新于2025-09-23 15:23:52
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[IEEE 2018 5th International Conference on Systems and Informatics (ICSAI) - Nanjing, China (2018.11.10-2018.11.12)] 2018 5th International Conference on Systems and Informatics (ICSAI) - An Improved Image Segmentation Method Based on Maximum Fuzzy Entropy and Quantum Genetic Algorithm
摘要： Image segmentation is a key technology in the image processing field. In the traditional image segmentation method, the selection of the threshold is the core of the image segmentation. In the fuzzy set theory, the fuzzy entropy is used to find the optimal threshold of the image segmentation. In this paper, the maximum fuzzy entropy is used to determine the optimal threshold of the image segmentation. The quantum genetic algorithm is used to find the optimal threshold of the image segmentation. The experimental results show that the image segmentation method based on maximum fuzzy entropy and quantum genetic algorithm has better segmentation effect and higher efficiency.
关键词： Quantum genetic algorithm,Fuzzy entropy,Image segmentation
更新于2025-09-23 15:22:29
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An improved 2D–3D model for charge transport based on the maximum entropy principle
摘要： To study the electron transport in a some tens of nanometers long channel of a metal oxide ?eld effect transistor, in order to reduce the computational cost of simulations, it can be convenient to divide the electrons into a 2D and a 3D population. Near the silicon/oxide interface the two populations coexist, while in the remaining part of the device only the 3D component needs to be considered because quantum effects are negligible there. The major issue is the description of the scattering mechanisms between the 2D and the 3D electron populations, due to interactions of electrons with nonpolar optical phonons and interface modes. Here, we propose a rigorous treatment of these collisions based on an approach similar to that used in Fischetti and Laux (Phys Rev B 48:2244–2274, 1993), in the context of a Monte Carlo simulation. We also consider all the other main scatterings, which are those with acoustic phonons, surface roughness, and impurities.
关键词： Semiconductors,2DEG,Quantum con?nement,Maximum entropy principle,Hydrodynamical models
更新于2025-09-23 15:22:29