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991.
Mg-implanted AISI 321 steel samples (implantation-energy 40 keV, dose: 2 * 1017 ions/cm2), were oxidized in air in the temperature region 350–650°C for several days. Nuclear Reaction Analysis (NRA) and Rutherford Backscattering Spectroscopy (RBS) were used to determine the oxygen concentration in the oxidized samples. An enhancement of the oxidation rate on the implanted material in comparison to the non-implanted was observed at high temperatures. It was demonstrated that the oxidation of Mg-implanted steel proceeds by two different mechanisms, at 350–550°C on the one hand and at 550–650°C on the other. The magnesium-depth distribution, determined by NRA (using the24Mg(, P)27Al reaction), RBS and X-ray Photoelectron Spectroscopy (XPS) also indicated a diffusion of the element at high temperatures confirming these assumptions. Scanning Electron Microscopy (SEM) and Scanning Transmission Electron Microscopy (STEM) were applied to investigate the surface morphology and to explain the influence of Mg-ion implantation on the oxidation behavior of AISI 321 austenitic stainless steel. 相似文献
992.
对Ni60合金粉末中添加B4C陶瓷颗粒的激光熔覆组织结构和力学性能做了研究。结果表明,加入陶瓷颗粒可增加熔覆层中强化相数量,提高涂层的硬度和耐磨性,在陶瓷颗粒加入量达到15%时效果最好。 相似文献
993.
钛阳极的制备及其纳米结构涂层的分析 总被引:4,自引:0,他引:4
唐电 《中国有色金属学报》1996,6(1):89-92
采用热分解方法,先在钛基上制取铱钴氧化物底层,然后再被覆钌铱钛锡氧化物涂层,获得晶粒尺寸小于10nm的涂层。 相似文献
994.
Copper was alloyed with small amounts of Al (0.2, 0.5, 1.0 and 2.0 mass%) to improve the oxidation resistance. Copper (6 N) and the Cu-Al alloys were oxidized at 773-1173 K in 0.1 MPa oxygen atmosphere after hydrogen annealing at 873 K. Continuous very thin Al2O3 layers were formed on the surface of all Cu-Al dilute alloys during the hydrogen annealing. Oxidation resistance of Cu-Al alloys was improved especially for Cu-2.0Al at 773-973 K, while it decreases on increasing the oxidation temperature. Cu-Al alloys followed the parabolic rate law at 1173 K, but most of other cases do not at and below 1073 K. Oxidation resistance for Cu-Al alloys was found relevant to the maintenance of the thin Al2O3 layer at the Cu2O/Cu-Al alloy interface. 相似文献
995.
996.
H.?H.?ParkEmail author M.?H.?Lee J.?S.?Yoon I.?S.?Bae B.?I.?Kim 《Metals and Materials International》2003,9(3):311-317
STS310S and SC-STS310S (simultaneously co-deposited chromium and aluminum onto 310S austenitic stainless steel substrate by
pack-cementation process) were used as separator materials on the cathode side of a molten carbonate fuel cell. With the STS310S,
corrosion proceeded via three steps; a formation step of unstable corrosion product, a protection step against corrosion until
breakaway, and an advance step of corrosion after breakaway. The final corrosion product was LiFeO2 and the loss of mass was 6.5 mg/cm2 after a corrosion test of 480 hr at 650°C. The SC-STS310S showed more effective corrosion resistance, however, than did common
STS310S. There was especially no corrosion loss on the SC-STS310S after the 480 hr corrosion test. It is anticipated that
it will be very useful as an alternative separator on the cathode side off the MCFC in the future. 相似文献
997.
CHENG Sujuan WANG Zhonghua QINXubo BAN Xiufang) Key Laboratory of Liquid Structure Heredity of Materials Ministry of Education Shandong University Jinan China) Mechanical Engineering Department Shandong University of Technology Zibo China) Shandong Dacheng Pesticide Co. Ltd. Zibo China 《稀有金属(英文版)》2003,22(3)
The structure of In-1%Cu and In-5%Cu (mass fraction) alloy melts were studied at different temperatures above liquidus by using a high-temperature X-ray diffractometer and were compared with that of pure In melt. Experimental results show that with the addition of 1% Cu or 5% Cu, the thermal contraction phenomenon of atom clusters occurs in melts with the temperature increasing like pure In melt. With the addition of 1% Cu, the thermal contraction of atom clusters increases and the contraction is not homogeneous in the whole measurement temperature range. The sudden change and noticeable contraction can be found in the range of 280-390℃. The temperature range of the sudden change is lower than that of pure In melt. With the addition of 5% Cu, the thermal contraction of atom clusters decreases and the contraction is not consistent in the whole measurement temperature range. The anomalous change can be measured at about 600 ℃. At the same superheating temperature, the nearest interatomic distance r1 of 相似文献
998.
进行了稀土对4Cr5MoSiVl钢硫氮碳共渗加氧化复合处理渗层热疲劳性能影响的研究结果表明,添加稀土的渗层比未添加稀土的热疲劳性能有显著提高。 相似文献
999.
A durable ceramic thermal barrier coating is applied directly to a smooth, highly oxidation resistant intermetallic alloy
in two layers. The first layer of ceramic is applied by low pressure plasma spraying and the second layer is applied by conventional
atmospheric pressure plasma spraying. This approach would allow the use of plasma sprayed ceramic coatings in applications
where a metallic bond coat is not desirable. 相似文献
1000.
以Ti-B4C-C团聚粉和Ni-Al“自粘结”复合粉的混合物为自蔓延反应火焰喷涂体系,在45钢基体表面制备Ti(Cx,Ny)-TiB2和NimAln梯度过渡的复相陶瓷涂层,分析研究了梯度过渡涂层的显微组织结构与耐磨性。研究表明:Ti(Cx,Ny)-TiB2复相陶瓷与NimAln金属间化合物实现了沿涂层厚度方向的梯度过渡连接。梯度过渡陶瓷涂层的耐磨性是普通45钢耐磨性的14倍。 相似文献