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Journal of Materials Science & Technology 2007年第2期23卷 201-206页

作者： Kaijin HUANG Xin LIN Changsheng XIE T.M. Yue State Key Laboratory of Plastic Forming Simulation and Mould Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Solidification Processing Northwestern Polytechnic University Xi＇an 710072 China Department of Industrial and Systems Engineering Hong Kong Polytechnic University Hung Hom Hong Kong China

The microstructure and wear behaviour of the thermite reaction coating produced by the hybrid laser claddingremelting on AA7075 aluminum alloy for the systems of Al-CuO-SiO2, Al-Cr2O3-SiO2, Al-Fe2O3-SiO2, and Al-TiO2-SiO2 were studied. The results of the X-ray diffraction （XRD） analysis show that in all the four reaction coatings, α-Al2O3 and γ-Al2O3 phases were present at the top surface, together with various intermetallic phases, the corresponding reduced metal and Al phase in the fusion zone. Under the dry sliding condition, the wear resistance, in terms of weight loss, of the laser-clad specimens was considerably higher than that of the untreated specimen. The predominant wear mechanism of the former specimens was abrasive wear, while for the latter, it was the adhesive wear that prevailed.

关键词： Laser cladding thermite reaction Aluminum alloy Wear

Microstructure and Wear Behaviour of Laser-Induced thermite reaction Al_2O_3 Ceramic Coatings on Pure Aluminum and AA7075 Aluminum Alloy

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Journal of Wuhan University of Technology(Materials Science) 2008年第1期23卷 89-94页

作者：黄开金 LIN Xin XIE Changsheng T M Yue State Key Laboratory of Plastic Forming Simulation and Mould Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Solidification Processing Northwestern Polytechnic University Xi＇an 710072 China Department of Industrial and Systems Engineering Hong Kong Polytechnic University Hung Hom Hong Kong China

Wear-resistant laser-induced thermite reaction Al2O3 ceramic coatings can be fabricated on pure Al and AA7075 aluminum alloy by laser cladding （one-step method） and laser cladding followed by laser re-melting （two-step method） using mixed powders CuO-Al-SiO2 in order to improve the wear properties of aluminum and aluminum alloy, respectively. The microstructure of the coatings was characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The wear resistance of the coatings was evaluated under dry sliding wear test condition at room temperature. Owing to the presence of hard α-Al2O3 and γ-Al2O3 phases, the coatings exhibited excellent wear resistance. In addition, the wear resistance of the coatings fabricated by two-step method is superior to that of the coatings fabricated by one-step method.

关键词： laser cladding thermite reaction aluminum alloy wear

Chemical reaction of In-situ Processing of NiAl/Al_2O_3 Composite by Using thermite reaction

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Journal of Wuhan University of Technology(Materials Science) 2005年第4期20卷 90-92,119页

作者：刘银 Department of Materials Science and Technology Anhui University of Science and Technology Huainan 232001 China

NiAl/Al2O3 composite were synthesized by thermite reaction of nickel oxide and aluminum powder *** phase,the microstructure of the composite,as well as the thermite reaction mechanism,were investigated by X-ray diffractomety（XRD0,scanning electron microscopy（SEM） combined with differential scanning calorimetry（DSC）.The experimental results show that the thermite reaction leads to the interpenetrating network structure of NiAl/Al2O3 at 1223K for 60min and the chemical reaction apparent activation energy is Eap=166.960±13.496kJ·mol^-1 in the NiO/Al system.

关键词： NiAl/Al2O3 composite thermite reaction apprarent activation energy

Spray deposition of FeCrNiMn and high carbon steel coatings by thermite reaction

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Journal of Central South University 2018年第12期25卷 2962-2970页

作者： CHEN Gang SHEN Shu-cheng NI Song ZHOU Chen-shang College of Materials Science and Engineering Hunan University State Key Laboratory of Powder Metallurgy Central South University

A novel surface cladding technique was developed to prepare the FeCrNiMn alloy and high carbon steel cladding layers,and the microhardness,bonding strength,abrasion wear and corrosion resistance were *** microstructures of the cladding layers were analyzed by using X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).The results show that the bonding strength between the substrate and the two cladding layers were(432.6±21)and(438.3±12)MPa,*** hardness values of the two cladding layers were HV418.5and HV329.6,*** corrosion current densities of the two coatings were2.926×10–6and6.858×10–6A/cm2after electrochemical corrosion test in3.5%NaCl solution,and the wear rate were1.78×10–7and1.46×10–6mm3/mN after sliding wear test,*** indicates that a well metallurgical bonding between the coating and the substrate was achieved,the abrasion wear and corrosion resistance of both coatings had been greatly improved compared with the *** novel cladding technology is promising for preparing wear-and-corrosion resistant coatings.

关键词： spray deposition thermite reaction coating corrosion property wear property

Mechanism for thermite reactions of aluminum/iron-oxide nanocomposites based on residue analysis

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Transactions of Nonferrous Metals Society of China 2014年第1期24卷 263-270页

作者：王毅宋小兰姜炜邓国栋郭效德刘宏英李凤生南京理工大学国家特种超细粉体工程技术研究中心南京210094 中北大学材料科学与工程学院太原030051 中北大学化工与环境学院太原030051

Sol-gel method was employed to combine Al and iron-oxide to form nanocomposites （nano-Al/xero-Fe2O3 and micro-Al/xero-Fe2O3）. SEM, EDS and XRD analyses were used to characterize the nanocomposites and the results indicated that nano-Al and micro-Al were compactly wrapped by amorphous iron-oxide nanoparticles （about 20 nm）, respectively. The iron-oxide showed the mass ratio of Fe to O as similar as that in Fe2O3. Thermal analyses were performed on two nanocomposites, and four simple mixtures （nano-Al＋xero-Fe2O3, nano-Al＋micro-Fe2O3, micro-Al＋xero-Fe2O3, and micro-Al＋micro-Fe2O3） were also analyzed. There were not apparent distinctions in the reactions of thermites fueled by nano-Al. For thermites fueled by micro-Al, the DSC peak temperatures of micro-Al/Xero-Fe2O3 were advanced by 68.1 ℃ and 76.8 ℃ compared with micro-Al＋xero-Fe2O3 and micro-Al＋micro-Fe2O3, respectively. Four thermites, namely, nano-Al/xero-Fe2O3, nano-Al＋micro-Fe2O3, micro-Al/xero-Fe2O3, and micro-Al＋micro-Fe2O3, were heated from ambient temperature to 1020 ℃, during which the products at 660 ℃ and 1020 ℃ were collected and analyzed by XRD. Crystals of Fe, FeAl2O4, Fe3O4,α-Fe2O3, Al,γ-Fe2O3, Al2.667O4, FeO andα-Al2O3 were indexed in XRD patterns. For each thermite, according to the specific products, the possible equations were given. Based on the principle of the minimum free energy, the most reasonable equations were inferred from the possible reactions.

关键词： Al Al nanocomposites thermite reaction reaction mechanism

Enhancing energetic performance of metal-organic complex-based metastable energetic nanocomposites by spray crystallization

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Defence Technology（防务技术） 2023年第6期24卷 203-213页

作者： Ke-xin Wang Li-xiao Shen Bin Yuan Yan Li Shun-guan Zhu Lin Zhang Zhen-xin Yi Chen-guang Zhu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210941China

Energetic metal-organic complexes have been involved in nanothermites as novel ***,the existing preparation methods often lead to mixing inhomogeneity and small contact area of ingredients,the reactivity and functionality of the novel energetic nanocomposites are still *** this work,spray crystallization(SC)method was used to prepare novel energetic nanocomposites,the high-energy metal-organic complex[Ni(CHZ)_(3)](ClO_(4))_(2)(CHZ=1,3-diaminourea)was composited with nanoaluminum(n-Al).Results showed that n-Al/[Ni(CH_(2))_(3)](ClO_(4))_(2)energetic nanocomposites prepared by SC method increased heat release to 2977.6 J/g and peak pressure to 3.91 MPa with higher pressurization rate(1324.06 MPa/s),decreased sensitivity thresholds(>100 mJ)to electrostatic discharge(ESD)and enhanced detonation ability compared with[Ni(CHZ)_(3)](ClO_(4))_(2)alone and physically mixed(PM)n-Al/[Ni(CHZ)_(3)](ClO_(4))_(2).These results proved that it is significant to introduce energetic metal-organic complexes with inherent high energy in new-concept n-Al/energetic metal-organic complexes nanocomposites through SC method for a better performance of its application.

关键词： Energetic metal-organic complexes Nano aluminum Energetic nanocomposites Spray crystallization thermite reaction

Combustion characteristics of aluminium-iron oxide in SHS-gravitational process

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Journal of University of Science and Technology Beijing 2002年第3期9卷 221-223页

作者： Tao Lin, Shiju Guo, Sheng Yin, and Zhimeng GuoMaterials Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China (Received 2001-10-15) Beijing Univ Sci & Technol Sch Mat Sci & Engn Beijing 100083 Peoples R China

In order to get high quality of products, the combustion of aluminium-ironoxide thermite in SHS-gravitational process must be under control. The effects of thermite fillingdensity, hole in thermite and inclined angle of pipe on combustion rate were studied. It shows thatthe combustion rate decreases with the decrease of filling density. The thermite combusts downwardsthe pipe much more quickly if there are holes in the thermite. And the combustion rate increaseswith the increase of the inclined angle of pipe. The experiment results show that the combustion ofthermite is predominantly controlled by gas phase reaction, which is attributed to the hightemperature of the thermite combustion.

关键词： thermite reaction SHS chemical synthesis composites

Depositing of Amorphous Ferri-oxide Nanoparticles on Surfaces of Submicron Aluminum Powder

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Depositing of Amorphous Ferri-oxide Nanoparticles on Surface...