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铝板水热碳吸附工艺制备APC/Al层状复合材料的显微组织、力学性能和摩擦学性能

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Transactions of Nonferrous Metals Society of China 2024年第1期34卷 108-121页

作者：陈奕涵许红雨姜博王晔胡茂良吉泽升哈尔滨理工大学材料科学与化学工程学院哈尔滨150080 哈尔滨理工大学先进制造智能化技术教育部重点实验室哈尔滨150080

采用铝板水热碳吸附工艺(HTCAP)和真空热压烧结工艺(VHPS)制备无定形碳(APC)/Al层状复合材料,研究葡萄糖溶液浓度对其显微组织、力学性能和摩擦学性能的影响。结果表明,APC在层间分布均匀,并且通过Al的扩散与基体形成良好的界面结合。... 详细信息

采用铝板水热碳吸附工艺(HTCAP)和真空热压烧结工艺(VHPS)制备无定形碳(APC)/Al层状复合材料,研究葡萄糖溶液浓度对其显微组织、力学性能和摩擦学性能的影响。结果表明,APC在层间分布均匀,并且通过Al的扩散与基体形成良好的界面结合。随着葡萄糖溶液浓度的增加,层间硬度、极限抗拉强度(UTS)和伸长率先增大后减小,而磨损率则呈现相反的趋势,摩擦因数(COF)逐渐减小。当葡萄糖溶液浓度为0.3 mol/L时,伸长率最大,为16.4%,磨损率最小,为0.344×10^(-5)mm^(3)/(N·m)。粘着磨损是APC/Al层状复合材料的主要磨损机制。耐磨性的提高是由于在磨损表面形成均匀的APC润滑膜。

关键词：铝基层状复合材料无定形碳水热反应界面显微组织摩擦学性能

Effects of cooling rate on vermicular graphite percentage in a brake drum produced by onestep cored wire injection

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China Foundry 2015年第5期12卷 349-353页

作者： Yu-shuang Feng ze-sheng ji He-sheng Wu Yong-cheng Feng School of Materials Science and Engineering Harbin University of Science and Technology Harbin Kedewei Metallurgy Co. Ltd. Shandong Ductile Iron Pipes Co. Ltd.

In this research, a vermicular graphite cast iron brake drum was produced by cored wire injection in a one-step method. Silica sand and low-density alumina-silicate ceramic were used as molding materials in order to investigate the effect of cooling rate on percentage of vermicular graphite and mechanical properties of the brake drum casting. Several thermocouples were inserted into the casting in the desired positions to measure the temperature change. By means of one-step cored wire injection, the two residual concentrations of Mg and RE were effectively controlled in the ranges of 0.013%-0.017% and 0.019%-0.025%, respectively, which are crucial for the production of vermicular graphite cast iron and the formation of vermicular graphite. In addition, the cooling rate had a significant effect on the vermicular graphite percentage. In the case of the silica mold brake drum casting, there was an obvious difference in the cooling rate with the wall change, leading to a change in vermicular graphite percentage from 70.8% to 90%. In the low-density alumina-silicate ceramic mold casting, no obvious change in temperature was detected by the thermocouples and the percentage of the vermicular graphite was stable at 85%. Therefore, the vermicular graphite cast iron brake drum with a better combination of mechanical properties could be obtained.

关键词： cored wire injection in one-step vermicular graphite cast iron cooling rate vermicular graphite percentage brake drum

Effect of different fillers on oxidation behavior of low-temperature chromizing coating

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Transactions of Nonferrous Metals Society of China 2014年第6期24卷 1785-1790页

作者：孟君晟吉泽升哈尔滨理工大学材料科学与工程学院哈尔滨150040 黑龙江科技大学材料科学与工程学院哈尔滨150022

Three different chromizing coatings were produced on Ni substrate using a conventional pack-cementation method with Al2O3,Al2O3＋CeO2 and CeO2 acting as filler,respectively,at a greatly decreased temperature（700 ℃）.Effects of different fillers on the isothermal and cyclic oxidation resistance of chromizing coating in air at 850 ℃ were comparably *** results show that the addition of CeO2 into the filler significantly retards the grain growth of the chromizing *** results indicate that the chromizing coating using CeO2 as filler exhibits somewhat increased oxidation resistance than the normal chromizmg coating,while the chromizing coating using Al2O3＋CeO2 as filler exhibits much better oxidation *** effects of different fillers on the oxidation behaviors were discussed in detail.

关键词： chromizing coating filler CeO2 oxidation reactive element effect

Effect of La_2O_3/Ce O_2 particle size on high-temperature oxidation resistance of electrodeposited Ni-La_2O_3/Ce O_2 composites

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Transactions of Nonferrous Metals Society of China 2014年第11期24卷 3571-3577页

作者：孟君晟吉泽升黑龙江科技大学材料科学与工程学院哈尔滨150022 哈尔滨理工大学材料科学与工程学院哈尔滨150040

Ni-La2O3/CeO2 composite films were prepared by electrodeposition from a nickel sulfate bath containing certain content of micrometer and nanometer La2O3/CeO2 particles. The effect of La2O3 or CeO2 particle size on the oxidation resistance of the electrodeposited Ni-La2O3/CeO2 composites in air at 1000 °C was studied. The results indicate that, compared with the electrodeposited Ni-film, Ni-La2O3/CeO2 composites exhibit a superior oxidation resistance due to the codeposited La2O3 or CeO2 particles blocking the outward diffusion of nickel. Moreover, compared with nanoparticles, La2O3 or CeO2 microparticles have stronger effect because La2O3 or CeO2 microparticles also act as a diffusion barrier layer at the onset of oxidation.

关键词： Ni-based composite electrodeposition high-temperature oxidation La2O3 CeO2 reactive element effect oxidation mechanism

Microstructure and Mechanical Properties of AZ91D Magnesium Alloy Recycled from Scraps by Hot-press/extrusion

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Journal of Harbin Institute of Technology(New Series) 2014年第1期21卷 115-120页

作者： Mao-Liang Hu ze-sheng ji Xiao-Yu Chen Qu-Dong Wang School of Materials Science and Engineering Harbin University of Science and Technology National Engineering Research Center for Light Alloy Net Forming Shanghai Jiao Tong University

A large number of scraps are produced in the fabrication process of magnesium alloy products. It is necessary to recycle these scraps for the development and scale application of magnesium alloys. In this research,a method for recycling AZ91D magnesium alloy scraps fabricated by hot-press / extrusion was studied. Mechanical properties and microstructure of the recycled specimens were investigated. Microstructural analyses were performed by using the techniques of optical microscopy and scanning electron microscopy. Microstructural observations reveal that the recycled specimens consisted of fine grains when adopting the extrusion temperature of 400- 450 ℃,the extrusion ratio of( 25- 100) ∶ 1 and the extrusion rate of 0. 10- 0. 20 mm / s. Ultimate tensile strength and elongation to failure increased with the increase of the extrusion temperature,the extrusion ratio and the extrusion rate,respectively. Recycled specimens reached the highest ultimate tensile strength of average 361. 47 MPa and the highest elongation to failure of average 11. 55% when adopting the hot-press,the extrusion temperature of 400± 5 ℃,the extrusion ratio of 100 ∶ 1 and the extrusion rate of 0. 15 mm / s. The shape of bonding interface was tightly relation with the ultimate tensile strength. When the bonding interface formed continuous curves,the ultimate tensile strength decreased almost linearly with increasing the average width of the bonding interface. When the bonding interface formed discontinuous curves,the ultimate tensile strength increased almost linearly with the increase the proportion of the fine bonding length accounting for the measured interface length. Ultimate tensile strength of the recycled specimens could be calculated by using the forecastable equation.

关键词： scraps magnesium alloy mechanical property bonding interface

Design and preparation of aluminum alloy with high thermal conductivity based on CALPHAD and first-principles calculation

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China Foundry 2022年第3期19卷 225-237页

作者： Ye Wang Hui-jun Kang Yu Guo Hong-tao Chen Mao-liang Hu ze-sheng ji School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150004China Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Dalian University of Technology)Ministry of EducationDalian 116024LiaoningChina Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024LiaoningChina School of Science and Engineering Huzhou CollegeHuzhou 313000ZhejiangChina

To obtain the aluminum alloy with high thermal and mechanical properties,the effects of alloying elements and the second phases on the thermal conductivity of Al alloys were investigated by CALPHAD and first-principles calculation,*** properties of the second phases,including Young's modulus,Poisson's ratio and minimum thermal conductivity,were systematically *** show that the ranking order of the effects of the alloying elements on the thermal conductivity is Mg>Cu>Fe>Si,and for Al-12Si alloys,the mathematical model of the relationship between the alloying elements and the thermal conductivity can be expressed as λ=ax^(2)-bx+c when the second phase precipitates in the *** kinds of ternary phases of Al-Fe-Si have higher deformation resistance,rigidity,theoretical hardness,Debye temperature and thermal conductivity than the other phases which possibly exist in the Al-12Si *** on the guidance of CALPHAD and first-principles calculation,the optimized chemical composition of Al alloy with high conductivity is Al-11.5Si-0.4Fe-0.2Mg(wt.%)with a thermal conductivity of 137.50 W·m^(-1)·K^(-1)and a hardness of 81.3 HBW.

关键词： design and preparation CALPHAD first-principles calculation thermal conductivity aluminum alloy

Reduction of shrinkage porosities in aluminum alloy castings by external pressure fluctuation under gravity field

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China Foundry 2018年第5期15卷 372-377页

作者： Shi-ping Wu Ru-jia Wang Ye Wang Wei Chen ze-sheng ji School of Materials Science and Engineering Harbin Institute of Technology School of Materials Science and Engineering Harbin University of Science and Technology

A novel method to improve the feeding capacity of ZL205 A alloy castings by pressure fluctuation during its solidification process under gravity field was proposed. The experiments were done in the graphite mould by applying the fluctuation pressure at the top of the riser. Results of the X-ray inspection of castings and simulations of flow velocity of alloy melt and temperature field show that the new method can effectively improve the feeding capacity and significantly reduce the shrinkage in the castings. The mechanism of improving the feeding capacity by pressure fluctuation is that the fluctuating pressure can make the ZL205 A alloy melt form a vibration wave in the melt. The vibration wave can intensify the convection of the melt, and therefore, break down the barrage from the feeding channel which forms during the solidification process of the ZL205 A alloy, improving the feeding capacity.

关键词： Fluctuation pressure shrinkage porosity ZL205A alloy gravity casting

High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： Man Zhang Xiao-Xu Liu Tian-Yi ji Yang Li Da-Wei sheng Shao-Dong Li Pei-Pei Ren ze-Xiang Shen School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone(ZIF) and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber(CoP@CF) were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g^(-1) at 0.1 A·g^(-1)after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·g^(-1).The sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Freestanding anodes Sodium-ion batteries

Benchmarking visual SLAM methods in mirror environments

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Computational Visual Media 2024年第2期10卷 215-241页

作者： Peter Herbert jing Wu ze ji Yu-Kun Lai School of Computer Science and Informatics Cardiff UniversityAbacws BuildingSenghennydd RdCardiff CF244AGUK School of Engineering Cardiff UniversityQueen’s BuildingsThe ParadeCardiff CF243AAUK

Visual simultaneous localisation and mapping(vSLAM)finds applications for indoor and outdoor navigation that routinely subjects it to visual complexities,particularly mirror *** effect of mirror presence(time visible and its average size in the frame)was hypothesised to impact localisation and mapping performance,with systems using direct techniques expected to perform ***,a dataset,MirrEnv,of image sequences recorded in mirror environments,was collected,and used to evaluate the performance of existing representative *** ORB-SLAM3 and BundleFusion appear to show moderate degradation of absolute trajectory error with increasing mirror duration,whilst the remaining results did not show significantly degraded localisation *** mesh maps generated proved to be very inaccurate,with real and virtual reflections colliding in the reconstructions.A discussion is given of the likely sources of error and robustness in mirror environments,outlining future directions for validating and improving vSLAM performance in the presence of planar *** MirrEnv dataset is available at https://***/10.17035/d.2023.0292477898.

关键词： visual simultaneous localisation and mapping(vSLAM) mirror localisation mapping reflection datase