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691.
用物理溅射法在碳纤维表面涂覆SiC 总被引:3,自引:0,他引:3
采用物理溅射法在碳纤维表面涂覆SiC,研究其工艺参数对涂层厚度及性能的影响。结果表明:该方法可在碳纤维表面得到均匀、连续的SiC涂层。当涂层厚度适当时,原纤维的强度不受影响,且工艺具有涂覆温度低,沉积速度快的特点。 相似文献
692.
CHEN Chen ZHANG Chun-xia GUO Hong-bo GONG Sheng-kai ZHANG Yue 《中国航空学报》2006,19(B12):82-85
Thermal barrier coatings (TBCs) were developed to protect metallic blades and vanes working in turbo-engines. The two-layered structure TBCs, consisting of NiCoCrAlY bond coat and yttria stabilized zirconia (YSZ), were deposited on a cylinder of superalloy substrate by the electron beam-physical vapor deposition (EB-PVD). The failure mechanism of the TBCs was investigated with a thermo-mechanical fatigue testing system under the service condition similar to that for turbine blades. Non-destructive evaluation of the coated specimens was conducted through the impedance spectroscopy. It is found that the crack initiation mainly takes place on the top coat at the edge of the heated zones. 相似文献
693.
XUE Wei YAO Zhong-ping JIANG Zhao-hua 《中国航空学报》2006,19(B12):126-129
Compound ceramics coatings on the Ti-6Al-4V alloy were prepared by the direct current micro-plasma oxidation (MPO) in NaAlO2 solution. The composition and morphology of the coatings were studied with the X-ray diffraction (XRD) and the scanning electron microscopy (SEM), respectively. Inductively coupled plasma atomic emission spectrometer technique was used to analyze the solution features of Ti-6Al-4V alloy in the process of preparation. The results reveal that Al2TiO5 forms in the coatings at the initial stages of MPO reaction, and its content changes rapidly with the reaction continuing: after 20 min, the ceramics coatings are composed of α-Al2O3, 7-Al2O3 and Al2TiO5, but after 40 min, its main composition is of α-Al2O3. The content of Ti in the solution will increase when the MPO time extends, and as will Al in the anode area until, after 30 min, it reaches the maximum and keeps constant from then on. Both substrata of Ti and Al in the electrolyte join the MPO reaction at the initial stage, where the formation of Al2TiO5 happens; but as the MPO reaction prolongs, more and more Al in the electrolyte will take part in the reaction, leading to the appearance of a large amount ofAl2O3. 相似文献
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Actively cooled thermal protection system has great influence on the engine of a hypersonic vehicle, and it is significant to obtain the thermal and stress distribution in the system. So an analytic estimation and numerical modeling are performed in this paper to investigate the behavior of an actively cooled thermal protection system. The analytic estimation is based on the electric analogy method and finite element analysis(FEA) is applied to the numerical simulation. Temperature and stress distributions are obtained for the actively cooled channel walls with three kinds of nickel alloys with or with no thermal barrier coating(TBC). The temperature of the channel wall with coating has no obvious difference from the one with no coating, but the stress with coating on the channel wall is much smaller than that with no coating. Inconel X-750 has the best characteristics among the three Ni-based materials due to its higher thermal conductivity, lower elasticity module and greater allowable stress. Analytic estimation and numerical modeling results are compared with each other and a reasonable agreement is obtained. 相似文献
699.
《航空制造技术》2012,(14):95
赛利涂层技术有限公司市场部副总经理张建明先生CemeCon与您展望未来第十一届中国国际机床工具展览会(CIMES2012)已经在北京新国际展览中心成功落下帷幕,赛利涂层技术有限公司(CemeCon)在此次展会中收益显著。CemeCon公司一直致力于为中国国内的切削刀具、工具、模具、零部件、电子等基础工业装备提供优质专业的表面硬化处理(PVD和CVD涂层)服务与技术支持。在展位集中展示了ALOXSN2HYPERLOX、HSN2等涂层产品,介绍了CC800/9、HPPMS系列涂层设备,以及赛利公司最新技术和研发成果。经过短暂的5天展出,我们得到了主办方及前来参展的各展商、观众和客户的大力支持。更增进了老客户对CemeCon公司今后产品服务质量的信心及信任,使新客户了解我公司在行业中的优势。展会期间,经过观众及客户的交谈中,我们了解到现阶段刀具行业的最新情况,了解到我们的涂层在不同的刀具上所体现出的不同的应用特 相似文献