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Nano Research 2022年第5期15卷 3866-3871页

作者： Zihao Xing Jun Li Shun Wang Chenliang Su Huile Jin Institute of New Materials&Industry Technology Wenzhou UniversityWenzhou 325024China Institute of Microscale Optoelectronics Shenzhen UniversityShenzhen 518060China

Platinum based alloys are hereinto the mostly used methanol oxidation catalysts.However,there are limited ways to improve the methanol oxidation reaction(MOR)performance of catalysts in terms of both activity and stability.Herein we developed a simple heat-treatment method to synthesize PtCu_(3)/C intermetallic compound catalyst with lattice compression.The as-prepared PtCu_(3)/C-1000 exhibited high specific activity of 3.23 mA·cm^(-1) and mass activity of 1,200 mA·mgPt^(-1),which is much higher than the PtCu_(3)/C-untreated and commercial Pt/C catalysts,respectively.The XAS and DFT results shows the high activity of the catalyst towards MOR comes from the tightening of the Pt-M bond,which leads to the decrease of Fermi energy level and the make it difficulty in adsorbing carbon intermediates,thus releasing more active sites to promote the improvement of MOR performance.Moreover,the PtCu_(3)/C-1000 shows better stability which is due to the surface-rich Pt prevents Cu from dissolution.

关键词： methanol electrooxidation PtCu_(3)alloy catalyst lattice compression composition reconstruction heat-treatment

Significantly improved corrosion resistance of Mg-15Gd-2Zn-0.39Zr alloys: Effect of heat-treatment

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Journal of Materials Science & Technology 2019年第8期35卷 1644-1654页

作者： Jing Liu Lixin Yang Chunyan Zhang Bo Zhang Tao Zhang Yang Li Kaiming Wu Fuhui Wang The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science in Metallurgical Process International Research Institute for Steel Technology Wuhan University of Science and Technology 947 Heping Avenue Wuhan 430081 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Shenyang National Laboratory for Materials Science Northeastern University 3-11 Wenhua Road Shenyang 110819 China

The effects of heat-treatment on corrosion behavior of Mg-15Gd-2Zn-0.39Zr alloys were investigated through microstructure characterization, corrosion tests, and scanning Kelvin probe force microscope(SKPFM) analysis. In long-term corrosion experiments, the corrosion rates of Mg-Gd-Zn-Zr alloys were mainly determined by the effects of micro-galvanic corrosion. During heat-treatment, the β-(Mg,Zn)3Gd eutectic phase in as-cast alloys transformed into a long-period stacking ordered(LPSO) phase, coupled with the precipitation of small precipitates. As heat-treatment proceeded, the local potential and the volume fraction of the LPSO phases reduced gradually compared with the eutectic phase, which resulted in a remarkable decrease of the micro-galvanic effect between the second phase and Mg matrix. As a result, the corrosion resistance of heat-treated alloys improved significantly.

关键词： Mg-Gd-Zn-Zr alloy Corrosion behavior heat-treatment LPSO phase SKPFM

Magnetic domain structures of precipitation-hardened SmCo 2:17-type sintered magnets: heat treatment effect

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Chinese Physics B 2008年第6期17卷 2281-2287页

作者：李岫梅方以坤郭朝晖刘涛郭永权李卫韩宝善 Division of Functional Materials Research Central Iron & Steel Research Institute State Key Laboratory of Magnetism Institute of Physics and the Center for Condensed Matter Physics Chinese Academy of Sciences

The typical magnetic domains of Sm（CObalFe0.25Cuo.07Zr0.02）7.4 magnets quenched through various heattreatment steps have been revealed by using magnetic force microscopy （MFM）. For the specimens in which the nominal c-axis is perpendicular to the imaging plane, the domain configurations change from plate-like for the as-sintered magnet to corrugation and spike-like for the homogenized one, and then to a coarse and finally to a finer domain structure when isothermally aged at 830℃ and then annealed at 400℃. However, only plate-like domains can be detected on the surfaces with the nominal c-axis parallel to the imaging plane. The finer domain （so-called interaction domain） is a characteristic magnetic domain pattern of the SmCo 2：IT-type magnets with high coercivities. Domain walls in a zigzag shape are revealed by means of MFM in final bulk SraCo 2：17-type sintered magnets.

关键词： Sm-Co permanent magnets magnetic domains heat-treatment magnetic force microscopy

Effect of heat treatment on Silica Aerogels Prepared via Ambient Drying

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Journal of Materials Science & Technology 2007年第3期23卷 402-406页

作者： Fei SHI Lijiu WANG Jingxiao LIU Miao ZENG Building Materials Research Lab Dalian University of Technology Dalian 116024 China Department of Materials Science and Engineering Dalian Institute of Light Industry Dalian 116034 China

Silica aerogels were prepared at ambient drying by using ethanol/trimethylchlorosilane （TMCS）/heptane solution as pore water exchange and surface modification of the wet gel before drying. The obtained silica aerogels exhibit a sponge-like structure with uniform pore size distribution. The effects of heat-treatment on the hydrophobicity, specific surface area and other properties were investigated. The results indicated that the hydrophobicity of silica aerogels could be maintained up to 350℃. With increasing heating temperature, hydrophobicity decreased, and became completely hydrophilic after heat-treatment at 500℃. Brunaueremmitt-teller （BET） surface area results indicated that the specific surface area of silica aerogels increased with increasing heating temperature in the range of 150-500℃. The effects of heat-treatment on the morphology and chemical bonding state of silica aerogels were investigated by scanning electron microscopy （SEM）, differential temperature analysis （DTA） and Fourier-transform infrared spectroscopy （FT-IR）.

关键词： Silica aerogel Ambient drying Hydrophobicity Specific surface area heat-treatment

Effect of Tube Spinning With Subsequent heat-treatment on Performance and Microstructure Evolution of T250 Maraging Steel

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Journal of Iron and Steel Research(International) 2012年第5期19卷 63-68页

作者： HU Zheng-fei WANG Chun-xu School of Material Science and Engineering Tongji UniversityShanghai 200092China China Iron and Steel Institute Group Beijing 100081China

The effects of spinning deformation and subsequent heat treatments on the mechanical properties and microstructure of 18Ni Co-free Maraging steel （T250） tube were evaluated comparatively with the perform. An obvious radial shrinkage is detected in spun tubes after heat treatment and the magnitude of the shrinkage induced by solution treatment is almost the same as that by aging. Plastic deformation during spinning elongated the grains severely in the direction of metal flow. The solution treatment resulted in a drastically refined grain and recrystallised microstructure, removing the effect of plastic deformation, relieving the tangential residual stress and strain and improving hardness. Subsequent aging obtained a tempered microstructure, enhancing hardness values strikingly for precipitation strengthening. XRD （X-ray diffraction） analysis indicated that the reversed austenite formed in a plate-like along the grain boundaries and the volume fraction of austenite in spun tube was more than double that in the preform. These results imply that the residual stress and stain induced by spinning process and reversed austenite forming during aging might have the similar contribution to the radical shrinkage.

关键词： maraging steel spinning process plastic deformation heat-treatment microstructure reversed austenite

Effect of heat-treatment Process on Properties of Rare Earth Mg-Based System Hydrogen Storage Alloys with AB_3-Type

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Journal of Rare Earths 2006年第Z2期24卷 340-342页

作者：王英卢其云彭能肖方明唐仁衡 Research Institute of Rare Metal Guangzhou Research Institute of Non-Ferrous Metals

The effect of heat-treatment process on the properties of Mm0.8Mg0.2(NiCoAlMn)3.5 hydrogen storage alloy was discussed. The electrochemical properties such as cycling stability, activation property, and the plateau voltage of the alloy which was heat-treated in various temperatures and times had different changes during the cycle process, the optimum heat-treatment conditions of this alloy were determined by this work.

关键词： heat-treatment rare earth Mg-based system hydrogen storage alloy Ni/MH battery

Effects of Steam heat-treatment on Properties of Pinus massoniana Wood and Its Bonding Performance

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Journal of Renewable Materials 2021年第4期9卷 789-801页

作者： Meifen Tian Bengang Zhang Zhigang Wu Liping Yu Lifen Li Xuedong Xi College of Forestry Guizhou UniversityGuiyang550025China Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products Southwest Forestry UniversityKunming650224China ENSTIB-LERMAB University of LorraineEpinal88051France

Pinus massoniana wood was modified by steam heat-treatment at 160℃,180℃,200℃ and 220℃ respectively and effects of the changes of density,pH,surface wettability and apparent morphology of Pinus massoniana heat-treated wood on its bonding performance were studied in this paper.The results showed that Pinus massoniana wood underwent a series of physical and chemical changes during heat-treatment as the the following:(1)The degradation of hemicellulose and cellulose with low degree of polymerization,degradation and migration of the extract resulting in the decline of density and pH of heat-treated Pinus massoniana wood.(2)Brittle fracture occured on the cell wall surface,and the pit collapse,shrink and deformation,resulting in the formation of roughness and porosity on the wood surface.(3)The surface energy decreased with the improvement of temperature,the surface wettability of Pinus massoniana wood treated at 160℃–180℃ was good,while that at 200℃–220℃ showed hydrophobicity.(4)Changes of density,pH,surface roughness and porosity,and wettability resulted in a reduction in the bonding strength and reliability of heat-treated Pinus massoniana wood with MUF resin adhesive.(5)When the temperature was at 160℃–180℃,the better wettability of heat-treated Pinus massoniana wood could guarantee the better bonding performance.

关键词： Pinus massoniana wood heat-treatment bonding performance

STUDY ON heat-treatment OF AIN/SiC_w COMPOSITES AND EFFECTS ON MICROSTRUCTURE AND PROPERTIES

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Journal of Wuhan University of Technology(Materials Science) 1998年第3期13卷 15-20页

作者：张宏泉 Wuhan University of Technology China Biomaterials Research Centre Wuhan University of Technology Wuhan 430070 China

AlN-SiC whisker composites with Y2O3 and SiO2 additives were heat-treated at 1300 ℃ in air. The phase composition and microstrurture were analyzed using XRD, SEM and HREM techniques to study the effect of heat-treatment on the microstructure and properties of the composites. The results reveal that the mechanical properties and high temperature oxidation resistance of the composite of ivhich additives composition approaches the eutectic point of Y2O3-SiO2 can be improved through the heat-treatment. Glass phase in the grain boundary is observed to react with the surface composition of AlN forming fibrous 2Hδ Sialon, resulting a crossing structure produced by fibrous 2Hδ Sialon and SiC whiskers.

关键词： AlN/SiC composties heat-treatment microstructure and properties

Effects of heat-treatment on Crystallization and Wear Property of Plasma Sprayed Fe-based Amorphous Coatings

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 643-646页

作者：姜超平 XING Yazhe HAO Jianmin SONG Xuding School of Materials Science and Engineering Chang'an University Key Laboratory of Road Construction Technology and Equipment MOE Chang'an University

The Fe-based amorphous coatings were produced by air plasma spraying. The as-sprayed coatings were heat-treated at the temperature of 573, 873, and 1 023 K, respectively. The crystallization and wear behavior of the heat-treated amorphous coatings were investigated. It was found that the amorphous- nanocrystalline transformation appeared when the as-sprayed coatings were treated at 853 K. The crystallization process had completed and a coating with microcrystallines was formed when the treatment temperature reached 1 023 K. The resultant amorphous and nanocrystalline composite coatings exhibited superior wear resistance compared to crystalline coating. It is attributed to fine grain strengthening of formed nanocrystallines.

关键词： amorphous air plasma spraying crystallization heat-treatment

Effects of Deformation and heat－treatment Process on Texture of Bi－2223／Ag Su perconducting Tapes

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Rare Metals 1996年第4期15卷 313-317页

作者：郭旭王超群袁冠森北京有色金属研究总院北京

The effects of deformation and heat-treatment on texture of BSCCO-2223/Ag tapes were investigatedby using single orientation quantitative texture analytical methods. The results show that when tapes weresintered at 835℃ for 24～48 h, the texture developed quickly, and further prolonging sintering tirne hadno significant influence on it. With the increase of deformation rate, the volume fraction of c-axis texturewas improved in linear form at first and then changed slowly. The highest volume fraction of c-axis texture(vol%)in these experiments is 33 . 49 % .

关键词： BSCCO-2223/Ag tapes Texture analysis heat-treatment