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991.
This communication reports into the effects of flow, fluid composition and the effectiveness of imidazoline inhibitors on the evolution and distribution of corrosion products on 1018 C-steel exposed to CO2 corrosion. Focused ion beam technique was used to measure the thickness of the corrosion product layer (CPL), in contrast to the conventional techniques used to observe the cross-section of specimens. Morphological analysis using scanning electron microscopy revealed topographical variations on the surface with the change in the multiphase environment. The CPL was found to be more porous in nature with the presence of oil in the multiphase environment. Electrochemical impedance spectroscopy was also used in the present study to measure the corrosion rates and was subsequently correlated to the CPL evolution for 1018 C-steel in multiphase environment. 相似文献
992.
M.A. Dar S.G. Ansari Z.A. Ansari Hironobu Umemoto Young-Soon Kim Hyung-Kee Seo Gil-Sung Kim Eun-Kyung Suh Hyung-Shik Shin 《International Journal of Refractory Metals and Hard Materials》2006,24(6):418-426
Diamond thin films have been deposited using hot filament chemical vapour deposition technique on manually scratched p-Si(1 0 0) substrate, with and without magnesium interlayer. In spite of magnesium melting point being lower (Tm = 649 °C) than the growth temperature of the substrate (Ts 750 °C) used in these experiments, it was found that high quality diamond films could be grown on Mg covered substrate. A liquid substrate is probably generated during the diamond film growth. Raman spectroscopy analysis exhibited only the triply degenerate, zone centre optical phonon peak at 1333 cm−1 indicating that nearly stress free crystallites were present. Broadening of the Raman peak (11.76 cm−1) indicates that some small crystallites also are present. Scanning electron and atomic force microscopy accompanied by X-ray diffraction analysis where used to compare the details of diamond film growth directly on scratched Si(1 0 0) and Mg interlayered scratched Si(1 0 0) substrates. 相似文献
993.
Application of electromagnetic-assisted stamping (EMAS) technique in incremental sheet metal forming 总被引:1,自引:0,他引:1
C.N. Okoye J.H. Jiang Z.D. Hu 《International Journal of Machine Tools and Manufacture》2006,46(11):1248-1252
The application of high velocity electromagnetic-assisted stamping (EMAS) technique in incremental sheet metal forming has been proposed. EMAS whose principle is based on Lorenz force is a hybrid forming process that uses both quasi-static conventional stamping technique and electromagnetic forming actuators built into sharp corners and other difficult-to-form contours to form metals. The recent push to use more artificial intelligent (AI) aluminum alloys in automobile and aircraft industries as a result of increasing demand for fuel efficient cars and aircrafts, large size vehicle panels, improved formability limit of materials and weight reduction have placed EMAS as one of the best high velocity forming technique.It is believed that the end result of this vision will lead to more cost effective land and aerospace vehicles. 相似文献
994.
Z. Serhal P. Berot J. Morvan M. Rezrazi J. Pagetti 《Surface & coatings technology》2002,150(2-3):290-296
Energy dispersive spectrometry (EDS) and infrared reflection absorption spectroscopy (IRRAS) have been previously used for the qualitative and quantitative analysis of PTFE in gold–PTFE composite coatings. The inclusion rate of PTFE particles in the composite coating is determined close to the surface by these two methods and particularly within a thickness of 0.5 μm by EDS. Differential scanning calorimetry (DSC) is investigated for a direct determination of the inclusion rate of PTFE, independently of the depth in the coating. The gold matrix allows us to release from metal oxidation and, associated with PTFE (chemically inert), to isolate easily the composite coating by dissolution of the metal support. Correlation is made between the DSC and EDS methods previously proposed as detection tools. 相似文献
995.
996.
Z. Huda 《Journal of Materials Engineering and Performance》1995,4(1):48-53
Recent advancements in turbine-blade materials engineering are reviewed in light of general superalloy research and the author’s
work on a new powder metallurgy IN-792 creep-limited alloy for application in blades of gas-turbine engines. The developed
set of principles presented in this paper incorporates all the factors that must be taken into consideration in selecting
and designing an alloy for turbine blades. 相似文献
997.
采用12Cr1MoV转炉钢生产高压锅炉钢管 总被引:1,自引:0,他引:1
介绍了转炉冶炼高压锅炉管钢工艺和采用12Cr1MoV 转炉钢生产的高压锅炉钢管性能。性能试验表明,转炉钢可以用于高压锅炉钢管生产,其实物质量与电炉钢相当。 相似文献
998.
Banding formation and eutectic lamellar growth in a directionally solidified Ni50Al20Fe30 alloy were investigated. It was found that the banding area consists of two layers. The first layer is a γ layer, while the
subsequent one is a γ layer. The composition of various phases around the banding area changes with the solidification process.
The banding is formed by two steps process and caused by factors such as the fractions during the sample growth process. It
was found that the band was found at relatively low growth rate. Therefore. this study indicates that increasing the growth
rate is an effective method to eliminate the band formation. Eutectic lamellae nucleate and grow again after the banding formation.
During the initial transition lamellar growth, the relationship between the square lamellar spacing, γ2, and the distance from, the banding, d, can be described by the following equation: γ2 = K [1-exp(A.d)] where K and A are constant. 相似文献
999.
This article discusses the cooling strategies for cryogenic machining from a materials viewpoint. It is argued that, because
different materials respond to temperature and machining processes differently, different cooling strategies are needed to
improve the machinabilities of materials by cryogenic machining. In this work, five workpiece materials such as AISI1010 low-carbon
steel, AISI1070 high-carbon steel, AISIE52100 bearing steel, titanium alloy Ti-6Al-4V, and cast aluminum alloy A390 were studied
experimentally at various temperatures. Based on the experimental results of the cryogenic properties of the materials and
their known machining characteristics, the cooling strategies for cryogenic machining of these materials were analyzed. 相似文献
1000.
A. Ohmori Z. Zhou K. Inoue K. Murakami T. Sasaki 《Journal of Thermal Spray Technology》1996,5(2):134-138
The penetration phenomena of liquid manganese (Mn) alloy into porous ZrO2 (8 vvt % Y2O3) coating plasma sprayed on SS400 steel substrate was studied by heating in a vacuum atmosphere. The improvement in mechanical
properties of the coating by heat treatment with liquid Mn alloys was examined. Liquid Mn alloys, such as Mn-Cu, Mn-Sn, and
Mn-In, rapidly penetrated the coating and formed a chemical bond between the coating and the substrate. The densification
of the ZrO2 coating occurred when ZrO2 particles were sintered with liquid Mn alloys that penetrated the porous coating. The dense coating was free of porosity,
and its hardness increased after heat treatment with Mn alloys, compared with assprayed ZrO2 coating. Moreover, the fracture toughness of the coating reached the same levels as those of sintered yttria-stabilized PSZ. 相似文献