Advanced Materials Research Vol. 803

Abstract: Ag nanoparticles (NPs) had most prominent local surface plasma resonance effect (LSPR) among the all metals. Diamond-like carbon (DLC) film had good biological compatibility, wear resistance, corrosion-resisting and high transmission ability in the visible and near-infrared range. Since the Ag NPs were easily oxidized in air,a new LSPR interface between them and an ultra-thin DLC films was formed by means of a plasma enhanced chemical vapor deposition (PECVD). The morphologies and properties of the Ag NPs deposited ultra-thin DLC films were studied by using Raman spectrometer, X-ray photoelectron spectrometer (XPS) , field emission scanning electron microscope (FESEM) and atomic force microscope (AFM) and so on. And the optical tramsmission sensitivity of the new LSPR interface was also examined. The results indicated that the DLC films deposited in a shorter time had a higher sp³ bond content of carbon atoms and more sensitive to refractive index of surrounding media. Moreover, to obtain the optimal morphologies and the sensing property, the deposition time for forming the DLC films should be controlled within 30 seconds.

Abstract: Al-3.9wt.%Cu alloy was subjected to equal channel angular pressing (ECAP) and subsequent low temperature annealing treatment, and the corrosion resistance of the samples was investigated by potentiodynamic polarization measurements in 3.5% NaCl solution. The results show that the corrosion rate of the ultrafine-grained alloy increases, in comparison with the coarse-grained alloy. Meanwhile, it is noted that the corrosion resistance of the alloy subjected to ECAP can be improved by relief annealing.

Abstract: The porous SiC-cordierite ceramics were prepared from SiC, calcined kaolin, talc, aluminum hydroxide, and graphite as pore-forming. The influence of pore-forming agent contents and sintering temperatures on the porosity and flexural strength of porous SiC-cordierite ceramics were investigated. The grain phases and the fracture surface micrograph were analyzed with XRD and SEM, respectively. The results show that the sample sintered at 1350°C for 3h with 15% graphite as the pore-forming agent exhibits the most excellent properties: flexural strength of 63.74MPa was achieved at a porosity of 31.80%.

Abstract: Cr-Nd coating was prepared by electrodeposition method. The microhardness, wear weight loss and friction coefficient of Cr-Nd coating were studied respectively. The Cr-Nd coating were characterized with ICP-AES, EDAX, XRD and SEM techniques, respectively. The micro-hardness and the wear weight loss, friction coefficient of the Cr-Nd coatings are higher and lower respectively than that of the Cr coating. The microhardness of the Cr-Nd is as high as 815.6 HV, which is higher 4.16% than that of the Cr coating (783.0 HV). The wear weight loss of Cr-Nd is lower 1.33 times than that of Cr coating. The friction coefficient of Cr coating and Cr-Nd coating are 0.896 and 0.714 respectively. There are crystalline CrC in Cr-Nd coating. There are nodules on Cr coating surface. There are not nodules on Cr-Nd coating surface. Cr-Nd coating surface is smooth.

Abstract: Jinchuan nickel-copper flash smelting slag is rich in iron, nickel, cobalt and copper, and JISCO converter slag is rich in iron, manganese and high CaO, etc., the two kind slags were blended, and then smelted into low-alloy iron containing nickel, cobalt, copper and manganese with smelting reduction method, which is a new comprehensive utilization methods for the Double slag. The thermodynamic calculation results of the equilibrium concentration of Fe, Cu and Ni in low-alloy iron obtained by smelting reduction under experimental condition are in good agreement with experimental results. Iron reduction rate of Fe, Cu and Ni can be elevated to above 90% by smelting reduction, thus the comprehensive utilization of valuable metals can come true.

Abstract: The internal friction of a cold-rolled Fe-Mn-Si alloy has been investigated using a multifunctional internal friction apparatus though forced vibration method from room temperature to 950 °C. It has been shown that an internal friction peak is found on the IF-T curves during first heating at around 640 °C for the cold-rolled Fe-Mn-Si alloy. The internal friction peak is confirmed to be crystallizing peak of amorphous. The amorphous is resulted from the cold-rolling of the Fe-Mn-Si alloy.

Abstract: Establishing large coal fired power, hydropower and wind power bases in the energy resources centre and large capacity long distance power energy transmission are main way to solve resource contradiction according to distribution characteristic of energy resource in our country. Power transmission line shall avoid influence of high altitude and low temperature etc environments in long distance power transmission, such as western area, the steel material of the fitting in the line with low temperature requirement shall have good low temperature resistant brittle, therefore the fittings in the power line are requested to have good low temperature resistant comprehensive performance. In combination with application environment of the power fittings and characteristics of metal material, carry out analysis on possibility of application of the low temperature resistant material in the fittings in the power line from performance requirements, fitting materials, geometrical features of the fittings, test characteristics of the fitting etc.

Abstract: The external locking device of a railroad switch is an important installation to lock switch rails and stock rails or wing rails by a switch machine. A locking bar can link with the actuator pole of the switch machine to finish switch and act in concert with the locking hook to lock the system. It is required adequate mechanical properties such as yield and fatigue strength. The text analyzes macro-feature of the fracture of a locking bar with failure and gets the conclusion that the locking bar fatigue fractured under alternating load. Metallographic structure and hardness of the material are also examined and found that quenching tends to be overheated with its poor hardenability. The solution is to improve the heat treatment method and increase the fatigue strength.

Abstract: Au nanoparticles arrays for silicon solar cells were fabricated by self-assembly method to accommodate manufacturing process of traditional silicon solar cells. Surface morphologies of 10-30 nm thick films after annealing treatment at 600 °C and 700 °C were analyzed. It indicated that morphological features of Au nanoparticles arrays such as particle shapes, size distribution vary with thicknesses of Au films, annealing temperatures and surface morphologies of substrates.

Abstract: a novel photovoltaic/thermal (PV/T) solar system was introduced in the paper, which consisted of both a flat plate solar thermal collector and a flat plate PV/T collector in parallel. Moreover, the effect of glass cover on PV/T collector was researched by theory and experiment. Experimental results show the daily average output efficiency of PV module reach 6.5% under condition without glass cover. But its output thermal efficiency is lower, and is only 26.4%. In addition, the daily average output efficiency of PV module and system thermal efficiency would reduce with the increase of the glass cover thickness under different glass cover thickness (2mm, 3mm and 4mm). Moreover, in the glass cover thickness of 2mm, the PV/T system had batter electricity and heat performance, and the daily average output efficiency of PV module and system thermal efficiency are 6.1%, 40.1%, respectively, the hot water temperature could reach 60°C. Hence, the PV/T solar system could meet the basic need of ordinary rural families in lighting electricity and hot water.