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钢纤维增强尾砂胶结充填体的力学性能与损伤机制

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工程科学学报 2025年第2期47卷 234-248页

作者：熊艳碧刘晓辉程海勇吴顺川张京刘伟铧庹儒军刘泽民昆明理工大学公共安全与应急管理学院昆明650093 华北科技学院安全工程学院廊坊065201 昆明理工大学国土资源工程学院昆明650093

为探究钢纤维(SF)对充填体的力学性能与损伤破坏机制的影响,以纤维增强尾砂胶结充填体(FR–CTB)为研究对象,研究SF掺量对充填体力学性能的影响,采用数字图像相关(DIC)技术监测试件的全场应变,跟踪试件的裂纹发展,此外,从微观层面进一步... 详细信息

为探究钢纤维(SF)对充填体的力学性能与损伤破坏机制的影响,以纤维增强尾砂胶结充填体(FR–CTB)为研究对象,研究SF掺量对充填体力学性能的影响,采用数字图像相关(DIC)技术监测试件的全场应变,跟踪试件的裂纹发展,此外,从微观层面进一步研究了SF对充填体的增强机理.结果表明,随着SF掺量和养护龄期的增加,FR–CTB的单轴抗压强度、劈裂抗拉强度以及抗剪强度均表现出了不同程度的增长,SF掺量为20 kg·m^(-3)时增强效果最好,但是当超过20 kg·m^(-3)后增强效果显著降低.钢纤维的存在较大程度上约束了充填体裂隙的扩展,削弱裂隙尖端应力集中,有效阻止了裂纹的扩展,改善整个试件的变形.此外,添加钢纤维后,尾砂颗粒、纤维和水化产物形成了一个完整且更致密的结构,在加载过程中由于SF与尾砂–水泥基体之间的相互作用,SF的增强作用主要体现在桥接和拔出行为,水化产物的存在增加了SF表面的粗糙度,从而增加了SF与水泥–尾砂基体之间的摩擦力来吸收外部载荷的能量,提高FR–CTB的力学性能.最后利用SPSS曲线估计建立各龄期充填体强度计算模型,模型精度较高,可对掺钢纤维充填体强度进行预测.

关键词：尾砂胶结充填体钢纤维力学性能损伤演化微观特征

The Phase Stability, Thermodynamics Properties and Electronic Structures of L12-Type Al3Sc and Al3Y under High Pressures

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Chinese Physics Letters 2014年第8期31卷 155-159页

作者：段永华黄波孙勇彭明军周生刚 SchoolofMaterialScienceandEngineering KunmingUniversityofScienceandTechnologyKunming650093 KeyLabofAdvanceMaterialsinRareandPreciousandNonferrousMetals(MinistryofEducation) Kunming650093

The phase stability, thermodynamics properties and electronic structures of L12-Al3Sc and Al3Y compounds under pressure up to 40 GPa are investigated by using first-principles within a local density approximation. The results of formation energies show that Al3Sc is more stable than Al3 Y and the stability of Al3Sc will be better with the increasing pressure. The Gibbs free energy, heat capacity, Debye temperature and thermal expansion coefficient are also investigated. The decreasing density of states at the Fermi level and the strengthening Sc/Y-d orbital hybridization with Al （s, p） under high pressure lead to the observed increase of the structural stability for L12-Al3Sc and Al3 Y under pressures.

关键词： Binary alloys

Mesoporous Silica Materials Synthesized via Sol-Gel Methods Modified with Ionic Liquid and Surfactant Molecules

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Chinese Journal of Chemical Physics 2008年第6期21卷 596-600页

作者： Cun-ying Xu Ru-lan Tang Yi-xin Hua Peng-xiang Zhang Kunming University of Science and Technology Kunming 650093 China

Mesoporous silica materials were synthesized via a sol-gel method employing a room temperature ionic liquid （1-butyl-3-methylimidazolium tetrafiuoroborate, [bmim][BF4]） as a new solvent medium and further modified with surfactant （hexadecyl-trimethyl-ammonium bromide, CTAB） as a pore templating material. The synthesized samples were characterized by the transmission electron microscopy, X-ray diffraction, and N2 adsorption-desorption techniques. The results indicated that the mesoporous silica synthesized by using [bmim][BF4] and CTAB as mixed templates showed better mesostructural order and smaller pore size, compared with mesoporous silica materials synthesized by using single [bmim][BF4] as template under the same conditions. This indicates that the presence of surfactant can affect the microstructures of silica prepared by＇the present synthesis method.

关键词： Mesoporous silica Ionic liquid Surfactant

Synthesis of indium tin oxide nano-polycrystalline powders by ultrasonic spray pyrolysis

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Rare Metals 2022年第10期41卷 3579-3584页

作者： Li-Hua Zhang Sheng-Hui Guo Chao-Jin Zhou Jin-Hui Peng Shao-Hua Ju Jian-Bo Lan Yunnan Provincial Key Laboratory of Intensification Metallurgy Kunming650093China Key Laboratory of Unconventional Metallurgy Ministry of EducationKunming650093China National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology Kunming650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming650093China

Indium tin oxide(ITO) nano-polycrystalline powders were prepared by ultrasonic spray pyrolysis(USP) method using a precursor solution of indium and tin chlorides in a simple one-step process without any post-heat treatment,additives and other complex *** morphology and crystal structure of ITO powders were studied by thermogravimetric and differential thermal analysis(TG-DTA),X-ray diffraction(XRD),energy-dispersive spectrometer(EDS),scanning electron microscopy(SEM),laser particle size analyzer(LPSA),transmission electron microscope(TEM),high-resolution transmission electron microscopy(HRTEM) and selected area electron diffraction(SAED),*** results indicate that pure cubic ITO solid solution could be obtained at and above the pyrolysis temperature of 600℃.Through adjusting the size of atomized precursor droplets,the particles with regular spherical shape and smooth surface are also *** spherical particles have a narrow size distribution with a dominant diameter size in the range of 0.52-1.28 μm,and the average value is 1.01 μ*** clear lattice fringes in HRTEM image confirm a polycrystalline structure of ITO particles with the growth direction along(222) direction.

关键词： Indium tin oxide Ultrasonic spray pyrolysis Nano-polycrystalline powder Chloride precursor

Chemical vapor deposition growth behavior of graphene

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International Journal of Minerals,Metallurgy and Materials 2022年第1期29卷 136-143页

作者： Jie Wang Tengfei Fan Jianchen Lu Xiaoming Cai Lei Gao Jinming Cai Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650093China Faculty of Science Kunming University of Science and TechnologyKunming 650093China

The optimized growth parameters of graphene with different morphologies,such as dendrites,rectangle,and hexagon,have been obtained by low-pressure chemical vapor deposition on polycrystalline copper *** evolution of fractal graphene,which grew on the polycrystalline copper substrate,has also been *** the equilibrium growth state of graphene is disrupted,its intrinsic hexagonal symmetry structure will change into a non-hexagonal symmetry ***,we present a systematic and comprehensive study of the evolution of graphene with different morphologies grown on solid copper as a function of the volume ratio of methane to hydrogen in a controllable ***,the phenomena of stitching snow-like graphene together and stacking graphene with different angles was also observed.

关键词： graphene chemical vapor deposition various morphologies dendrites methane

Power Density Distribution Simulation and Relevant Heat Effect Calculation of a High-power CO2 Laser with Low Order Modes

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Chinese Journal of Lasers 2002年第5期11卷 15-21页

作者：李俊昌马琨樊则宾 Kunming University of Science and Technology Kunming 650093

The vertical excitation axial flux kilowatt CO 2 laser is an equipment widely used in the high power laser heat treatment industrial applications. The experimental measurements indicate that the power density distribution of laser beam is generally of ring distribution with a sunken at the center, therefore the laser beam cannot be simply regarded as base mode Gaussian beam. In this paper, such laser beam is regarded as the non interference superposition of TEM 00 and TEM 01 mode beams, the method to determine the simulation parameters is discussed, and the relevant heat effect calculation equation is deduced.

关键词： laser heat treatment thermal field

Studies on High Temperature Oxidation of Electrodeposited RE-Ni-W-P-SiC Composite Materials

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材料热处理学报 2004年第05B期25卷 1126-1129页

作者： ZHUXiao-yun XURui-dong GUOZhong-cheng TheCenterofNewMaterialsandSurfaceEngineeringResearchandDevelopment KunmingUniversityofScienceandTechnologyKunming650093PR.China

The oxidation of the Electrodeposited RE-Ni-W-P-SiC Composite materials at high temperature is investigated. The results show that during high temperature oxidation the relationship between the mass change of pure Ni, Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings and the oxidation time follows a mixed curve, i.e. it is approximately a linear relationship when the oxidation time is less than 60 mins while it is a power function relationship when the oxidation time is over 60 mins. The order for the oxidation rate of the four coatings is Ni> Ni-W-P> Ni-W-P-SiC>RE-Ni-W-P-SiC. The mass change of Ni-W-P, Ni-W-P-SiC or RE-Ni-W-P-SiC coatings increases exponentially with a rise of oxidation temperature. The high temperature-oxidation resistance of RE-Ni-W-P-SiC composite material is 3-4 times than that of Ni-W-P alloy coating. The cross section morphologies and X-ray diffraction patterns indicate that the high temperature-oxidation resistance of RE-Ni-W-P-SiC composite coating is better than any other coatings.

关键词：高温氧化 RE-Ni-W-P-SiC 复合材料显微结构电镀层

Separation of Cobalt from Iron by Chloride Hydrolysis at Elevated Temperature

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Journal of Materials Science & Technology 1997年第5期13卷 421-424页

作者： Ma, KY Zhu, ZZ Yan, CY Kunming University of Science and Technology Kunming 650093 China

The hydrolysis rate of Go-bearing ferrous chloride at elevated temperature and the conditions of separation of Co from Fe have been investigated. The hydrolysis process is comprised of the interfacial chemical reaction and the intra-grain diffusion. At the stage under the control of the interfacial chemical reaction, the apparent rate constant k equals to 198.79exp(-80.57/RT). The effects of the temperature, the partial pressure ratio of water vapor and the reaction time on the Co recovery and the separation of Co from Fe are examined. The optimum hydrolysis conditions are determined.

关键词： Cobalt metallurgy

Thermodynamic analysis and dynamics simulation on reaction of Al_2O and AlCl_2 with carbon under vacuum

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Journal of Central South University 2016年第2期23卷 286-292页

作者：卢勇周岳珍陈秀敏李紫勇郁青春刘大春杨斌徐宝强 National Engineering Laboratory for Vacuum Metallurgy(Kunming University of Science and Technology) Kunming 650093China Yunnan Provincial Key Laboratory of Nonferrous Vacuum Metallurgy Kunming 650093China

The feasibility study of the AlCl(g) generated by Al_2O-AlCl_2-C system under vacuum was carried out by thermodynamic analysis and CASTEP package of the Material Studio program which was based on density functional theory(DFT) formalism. Thermodynamic calculations indicate that Al Cl and CO molecules can be formed under conditions of temperature 1760 K and the pressure of 60 Pa. The interaction of Al_2O and AlCl_2 with C shows that the chemical adsorption of Al_2O and AlCl_2 does take place on C(001) crystal plane, and at the same time, new chemical bond is formed between Al atom in Al_2O and Cl atoms from one of the Al—Cl bonds in AlCl_2. The results, after 1.25 ps dynamics simulation, indicate that adsorbed Al Cl molecules are generated and CO molecule will be formed in this system, and they will escape from C(001) surface after a longer period of dynamic simulation time. It means that the reaction of Al_2O and AlCl_2 with C can be carried out under given constraint condition.

关键词： Ab initio molecular dynamics carbothermic-chlorination (AlCl2) reaction thermodynamics interaction Al2O