The corrosion behavior of pure Mo and three Mo-Al alloys containing 28, 50, and 75 atom % Al was studied over the temperature range of 800-1000°C in a H2/H2S/H20 gas mixture. Except for the Mo-50A1 alloy consisting of a two-phase structure of Mo3A1 and Mo3Al8, other alloys studied were single phase. The corrosion kinetics followed the parabolic rate law in all cases, regardless of temperature and alloy composition. The parabolic rate constants increased with increasing temperature but decreased with increasing Al content. The Mo-75A1 alloy exhibited the best corrosion resistance among all alloys studied, whose corrosion rates are 2.1-3.0 orders of magnitude lower than those of pure Mo (depending on temperature). A layer exclusively of MoS2 formed on pure Mo, while heterophasic scales were observed on Mo-Al alloys. The scales formed on Mo-28A1 consisted of n-Al203 and MoS2 at T 900°C and of a-A1203, MoS2, and A1055Mo2S4 at 1000°C, while the scales formed on Mo-5OAl consisted of mostly a-A1303 and a minor amount of MoS2. The scales formed on Mo-75Al consisted exclusively of a-Al203 at T 900°C and of mostly a-Al203 and a minor amount of MoS2 at 1000°C. The formation of a-A1303 is responsible for the significant reduction of the corrosion rates as compared with those of pure Mo. Infroduction Metal-aluminides have recently been considered for use ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 134.129.120.3 Downloaded on 2015-06-04 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 134.129.120.3 Downloaded on 2015-06-04 to IP

This paper describes the performance of Ni-P and Ni-Mo-P alloy coatings deposited by electroless plating on the aluminum alloy 5052 to evaluate the corrosion resistance, thermal stability and electro-conductivity of coating assemblies. Corrosion behaviors of the obtained deposits in a 0.5M H2SO4 environment were investigated. The crystalline state and morphologies of Ni-P and Ni- Mo-P alloys were examined by field emission scanning electron microscopy (FE-SEM). The experimental results indicate that the Ni-Mo-P coating operated at 70°C and pH 9.0 has a nanocrystalline structure and its corrosion resistance in a 0.5M H2SO4 environment can be enhanced by the co-deposition of Mo as compared to Ni-P films. It has also been found that the Ni-Mo-P ternary alloys reveal good thermal stability after annealing at 400°C. Based on the excellent performance of Ni-Mo-P ternary alloys, these alloys have a potential to be applied to precision mould, optical parts mould, and surface metallization of substrates.

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The energy materials such as titania (TiO2) and alumina (Al2O3) are the environmental friendly materials. In this paper the nanostructure of high surface area titania and alumina are fabricated by anodization process and assistance in electrochemical mold. In general, academic or research institutes can simply control the required experimental conditions in a small sample; however, it’s difficult to control the stable parameters in a large surface and a large number of nanostructural products in the industry production. In order to solve the problems of unstable current density and temperature we have designed a cooling functional electrochemical mold which can improve the nanostructural quality of energy materials during a large number production. The electrochemical mold is used for a local surface treatment at an isothermal temperature controlling. The mold limits sample for a specific treated area and current density in the electrolyte. The mold can be used for the assistance of electrolysis, electro-polishing, electro-deposition, anodization, etching, chemical deposition, pickling, and caustic processes. The mold structure includes fixture group, water-cooling electrode group, and electrode conductive group.