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钛-钢扩散复合界面组织与结合强度 总被引:1,自引:1,他引:1
将钛管、钢管利用冷拔-内压扩散法制备了内包覆钛-钢复管.用扫描电镜、能谱分析、X-光衍射和拉剪试验等方法,研究了扩散退火温度与时间对钛-钢扩散复合界面附近组织、成分和界面剪切强度的影响.结果表明,该制备方法可使钛-钢实现冶金结合;界面剪切强度随扩散温度升高先增加后减小;750-800℃×0.5h扩散退火界面剪切强度最高,可达210MPa左右;扩散退火中Fe、Ti原子发生了互扩散;界面上有TiC形成;750℃×0.5 h扩散退火试样断口未检测到TiFe、TiFe2相;900-950℃×0.5h扩散退火钢侧出现柱状晶区,钛侧出现无晶界晶区与针状马氏体晶区. 相似文献
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采用等离子喷涂工艺,制备了Mo丝增强的NiAl基单层复合材料。系统地研究了该复合材料的显微组织,Mo丝/NiAl界面的结合特性以及在不同热处理状态下复合材料的界面行为。研究表明:制备态单层复合材料的基体由强烈变形(扁平化)和高速结晶的NiAl熔滴颗粒形成的层状结构构成,颗粒间有较多的分界面,Mo丝/基体的界面结合强度不高,其结合为非冶金结合。800℃,3h退火后,Mo丝/基体界面的结合情况得到改善,复合材料的性能提高。更高温长时处理后,基体元素Ni在Mo丝中形成扩散层,在界面处基体一侧和基体中结晶的熔滴颗粒分界面处的铝的氧化物层明显增厚。 相似文献
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采用粉末轧制工艺,在界面添加4% Si粉进行界面微合金化调控,成功制备出界面结合良好的钢-铝复合材料.研究了界面微合金化设计、扩散退火处理工艺对钢-铝复合材料界面区元素扩散、生成物相的影响规律,探讨了元素Si界面调控的作用机理.结果表明:添加4% Si粉界面微合金设计,在500℃扩散退火,保温1h热处理工艺下,复合材料界面未出现金属间化合物,600℃扩散退火,保温1h热处理工艺下,仅出现少量化合物Fe2Al5,Si粉界面微合金化处理能延缓界面化合物相生成,使生成Fe2Al5相的扩散温度向高温推移;Si扩散固溶到Fe、Al基体中形成连续固溶体,提高了界面两侧物理及力学性能的连续性,改善复合材料的界面结合. 相似文献
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将TA1/5052爆炸焊接复合板在350、400及450 ℃分别保温1、3、6、9 h退火,对退火前后复合板组织和性能进行分析。结果表明:随退火温度升高,原子扩散加剧,界面形成的扩散层逐渐变厚;退火过程中铝易于向钛侧扩散,白色亮带和柯肯达尔孔洞主要位于靠近界面的5052铝合金侧;退火前界面处物相组成为α-Ti、α-Al、TiAl3,经350、400 ℃退火3 h及450 ℃退火1、3、6、9 h后,物相组成不变。经不同温度退火后,复合板界面抗拉强度低于退火前,而断面收缩率和伸长率明显高于退火前。拉伸断口分析表明,复合板TA1侧为以脆性断裂为主、韧性断裂为辅的韧脆混合断裂,5052侧为韧性断裂;复合板在350 ℃退火时界面剪切强度和剥离强度最大,较爆炸态分别增加8.24%和45.68%,随退火温度升高,界面剪切强度和剥离强度降低。退火前后界面结合区硬度均高于基复板两侧硬度,且随离界面距离增加,硬度逐渐降低直至降至钛铝两侧母材硬度。退火后界面结合区硬度明显低于爆炸态硬度。 相似文献
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对固-液法制备的铜铝复合板进行不同工艺的轧制并进行300℃×4h退火处理,测定了复合板的抗拉强度、伸长率、界面剥离强度及电导率,利用金相显微镜和扫描电镜等分析了结合界面的组织形貌,研究了轧制及退火工艺对结合界面扩散层组织和复合板性能的影响。结果表明,轧制后形成的CuAl2相降低了复合板的剥离强度和电导率,退火处理可促进结合界面原子互扩散形成Cu9Al4,改善复合板的性能,同时电导率也得以提高。 相似文献
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由于贵金属材料具有独特的抗腐蚀性、生理上的无毒性、良好的延展性以及生物相容性,它在医学领域的应用日益拓展。作者在本文着重介绍贵金属材料在牙科(包括牙科汞齐合金和铸造合金)、针灸、体内植入的电子器件及医用生物传感器等方面的研究与发展,分析了牙科用贵金属材料的演变过程等。 相似文献
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It is very important to study the corrosion behavior of composite brake materials for their design, manufacture, and application. In the study, one kind of composite brake material used in engineering machinery, two kinds used in automobiles, and gray cast iron HT200 were selected as tested materials. Their corrosion behavior in typical acid solution, alkali solution, salt solution, running water, and air were investigated. The results showed that some components of composite brake materials, such as iron matrix, steel fiber, and iron powder, were easily subject to corrosion in acid solution. Corrosive pitting, net‐like cracking, and breakage appeared at their corrosion surfaces, and in the solution of 3.5% NaCl, corrosive pitting took place and corrosion holes of 2–8 µm diameter formed at the corrosion surface of these components. But when brake materials were exposed to the solution of 5% NaOH, the organic binder was corroded seriously, nearly parallel cracks formed at the corrosion surface and some samples even became loose powders because the corrosion makes the binder lose its adhering function. In running water and air, the tested samples have an excellent corrosion resistance, and the composite brake material containing organic binder has a better corrosion resistance compared with other tested materials. The investigation has also indicated that the interface between ingredients easily corrodes. 相似文献
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M. Lei H.Z. Zhao H. Yang B. Song L.Z. Cao P.G. Li W.H. Tang 《Journal of Alloys and Compounds》2008,460(1-2):130-137
We design a facile and efficient solid-state reaction method by selecting an organic reagent dicyandiamide and metal oxides as precursors to prepare metal nitrides, carbides and rare-earth metal dioxymonocarbodiimides in sealed ampoules. Some fine divided nitride and carbide nanoparticles with small and uniform size can be easily obtained at the relatively low temperatures. It is interesting to find that dicyandiamide is not only a highly efficient nitridation reagent but also a highly efficient carburization reagent, and can be used as a precursor to directly synthesize rare-earth metal dioxymonocarbodiimides. A possible mechanism is proposed to explain the results of the reactions between the organic reagent and metal oxides. 相似文献
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I. Kuryliszyn-Kudelska B. Had?i?D. Sibera M. Rom?evi?N. Rom?evi? U. NarkiewiczW. Dobrowolski 《Journal of Alloys and Compounds》2011,509(9):3756-3759
The aim of the present work is to study the magnetic properties of ZnO(Fe) nanocrystalline samples prepared by two methods of synthesis. We have used the microwave assisted hydrothermal synthesis and traditional wet chemistry method followed by calcination. The detailed structural characterization was performed by means of X-ray diffraction and micro-Raman spectroscopy measurements. The dynamic magnetic properties were studied by means of AC susceptibility χ. The measurements were performed at small AC magnetic field with amplitude not exceeding 5 Oe and different frequency values (from 7 Hz to 9970 Hz). The AC susceptibility maxima have been found for in-phase susceptibility Re(χ) and for out of phase susceptibility Im(χ). We analyzed the observed frequency dependence of the peak temperature in the AC susceptibility curve using the empirical parameter Φ that is a quantitative measure of the frequency shift and is given by the relative shift of the peak temperature per decade shift in frequency, as well as Vogel-Fulcher law. 相似文献
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W.K. TanK. Abdul Razak K. Ibrahim Zainovia Lockman 《Journal of Alloys and Compounds》2011,509(24):6806-6811
Oxidation of Zn foil at temperatures of 100-400 °C was carried out in air to produce ZnO with various nanostructures. The final morphology of the oxidised Zn foil is largely dependent on the oxidation temperatures. At less than 300 °C, spherical oxide grains are seen. At 400 °C, 50 nm thick, porous nanosheets were formed after 30 min of oxidation. In portions of the samples, nanorods can be seen with diameters <10 nm and lengths reaching 1 μm. The nanosheets were formed in accordance to a vapour-solid mechanism whereas the nanorods were formed by diffusion of Zn through a certain path leading to the rod structure. At 450 °C, the nanorods became much more uniform. Oxidation at 500 °C resulted in ZnO nanorods. The rods are also blunt with smaller rods seen to branch out from the main rod. The luminescence properties of the ZnO were investigated as a function of the morphology of the oxide. Both green and blue emissions are seen for the samples with nanosheets whereas the nanorods ZnO has mostly green emission. 相似文献
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S. Lorentzou A. Zygogianni K. Tousimi C. Agrafiotis A.G. Konstandopoulos 《Journal of Alloys and Compounds》2009,483(1-2):302
The present study deals with Aerosol Spray Pyrolysis (ASP) synthesis of two families of nanostructured redox materials targeted to two different environmental applications: transition-metal-doped ferrites and base metal-doped cerium oxide, used for hydrogen production through solar-assisted water splitting and for catalytic soot oxidation, respectively. The synthesized powders were characterized with respect to their phase composition, morphology and particle size distribution by XRD, SEM and TEM analysis, which have shown their nanostructured character. Doped ferrites were evaluated, with respect to their hydrogen production activity from water dissociation, in an in-house built water-splitting testing rig. ASP materials proved to be very active water splitters demonstrating higher water conversion and hydrogen yields than materials of the same composition synthesized through Solid State Synthesis (SSS), with material performance depending on the dopants’ kind and stoichiometry. Base metal-doped cerium oxides were evaluated with respect to their direct soot oxidation activity, via Thermogravimetric Analysis (TGA), as well as on a diesel engine bench under realistic conditions. It was found that doping improves their activity and that they enhance soot oxidation at lower temperatures compared to materials synthesized through Liquid Phase Self-propagating High temperature Synthesis (LPSHS). 相似文献
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