Effect Of Plate Temperature Research Articles

The effects of electrodeposition temperature on morphology and corrosion resistance of calcium phosphorus coatings on magnesium alloy: comparative experimental and molecular dynamics simulation studies.

In this study, CaP coatings were prepared on the surface of an AZ31B magnesium alloy using electroplating in order to slow down the degradation rate of magnesium alloy in the simulated physiological environment. The effect of plating temperature on the properties of CaP coatings was investigated by combining experimental techniques with molecular dynamics (MD) simulation. The surface morphology of CaP coatings changed from dendritic lamellar to granular structure with the increase of plating temperature, but the main structure of CaP coatings prepared at all temperatures was CaHPO4·2H2O. The CaP coatings prepared at 60 °C have higher corrosion resistance compared to coatings prepared at other temperatures. The MD simulation revealed the DCPD/Mg interfacial binding mechanism, and DCPD/Mg could form a stable interfacial layer at different temperatures because the binding energy was negative. HPO42- and H2O groups in the DCPD structure acted as riveting groups in the interfacial layer and formed Mg-HPO42- and Mg-H2O dipole pairs with Mg respectively through electrostatic interaction and van der Waals forces. The interfacial bonding energy between DCPD/Mg reached its lowest at 60 °C and the relative contents of HPO42- and H2O in the interface layer were the highest at this temperature, which may explain the high corrosion resistance and high bonding force of CaP coatings prepared at this temperature.

Microstructure and electrical conductivity of electroless copper plating layer on magnesium alloy micro-arc oxidation coating

In order to impart electrical conductivity to the magnesium alloy micro-arc oxidation (MAO) coating, the electroless copper plating was performed. Effects of plating temperature and complexing agent concentration on the properties of the electroless copper plating layers were studied by measuring their microstructure, corrosion resistance and electrical conductivity. It was found that the optimized plating temperature was 60 °C, and the most suitable value of the complexing agent concentration was 30 g/L. Under this condition, a complete and dense plating layer could be obtained. The formation mechanism of the plating layer on magnesium alloy MAO coating was analyzed. A three-stage model of the plating process was proposed. The square resistance of the plated specimen was finally reduced to 0.03 Ω/□ after the third stage. Through electroless copper plating, the MAO coated sample obtained excellent electrical conductivity without significantly reducing its corrosion resistance.

Light-Induced Al Plating on Si for Fabrication of an Ag-Free All-Al Solar Cell

Light-induced electroplating of Al as the front electrode on the n-type emitter of Si solar cells is proposed as a substitute for screen-printed Ag. The advantages and disadvantages of Al over Cu as the front electrode are discussed. The power of a green laser used for patterning of the SiNx antireflection coating is optimized. Conditions for removal of laser damage and contamination on the laser-patterned surface are identified. The effect of plating temperature and post-annealing temperature on Al morphology and resistivity are investigated. Several plating additives are explored to improve the morphology and resistivity of the Al film. Nicotinic acid produces the lowest resistivity of 3.1 μΩ-cm. However, the lowest contact resistivity between light-induced Al and Si is 69 mΩ-cm2 due to laser-induced damage to the emitter. The Al film spikes through the thin n-type emitter when annealed at 500 °C causing cell failure. The process reproducibility is also poor due to atmospheric moisture.

Experimental investigation of heat transfer characteristics during water jet impingement cooling of a high-temperature steel surface

ABSTRACT The microstructure and mechanical properties of the hot rolled steel depend on the laminar jet cooling control on the runout table. An experimental and numerical study of the heat transfer during water jet impingement cooling of a hot steel plate (600 to 900°C) is presented. The effects of plate temperature upon the heat transfer were analyzed by the inverse heat conduction method that provided the heat fluxes on top surface from measured temperatures into the plate. Rewetting (liquid-solid contact) occurs on surface above 880°C. Higher initial temperatures enlarge the heat flux, but delay the onset of the rewetting and the advance of rewetting front radius (Rwet). Heat transfer coefficient (HTC) increases as surface temperature decreases. The size of the non-symmetric effective jet cooling zone depends on strip speed. Correlations to predict HTC and Rwet have been proposed. Results will contribute for enhancement of fast cooling system in hot strip mill.

Effect of temperature on ultrasound-assisted electroless nickel-boron plating

Electroless nickel-boron coatings have several advantages over electroplated nickel and electroless nickel-phosphorous: they are harder than both other coatings and, as all electroless coatings, can be applied easily to complex shapes and all substrates, even non conducting ones, contrary to electroplated coatings. Preliminary testing has proved that ultrasound assistance helps improve their properties by increasing the plating rate while conserving the properties of the coating.In this study, the effect of plating temperature on mechanically agitated and ultrasonic assisted electroless nickel-boron deposition was investigated: deposition was performed in two different configurations: one with a classical mechanical agitation at 300 rpm and the other employing ultrasound at a frequency of 35 kHz. In addition, different temperatures in the 80–95 °C range were tested. The increase of plating rate previously observed was confirmed and it was possible to lower slightly plating temperature while conserving plating efficiency, which decreases evaporation of the solution. Morphological, mechanical, corrosion and wear characterization were performed on the coatings, as well as tribocorrosion studies in an alkaline environment (0.1 M NaCl). Ultrasound-assisted coatings presented tribocorrosion behaviour that was similar or better than the standard ones.

Light-Induced Plating of Aluminum on Silicon in an Ionic Liquid

As the consumption of silver for the front electrode in silicon solar cells continues to grow rapidly, a low-cost low-resistivity Earth-abundant metal is likely needed to replace silver. Besides the widely-studied copper, aluminum is another candidate for front metallization in silicon solar cells. Conventional electroplating of aluminum in a nonaqueous ionic liquid has been carried out on silicon solar cells and about 18% efficiency has been demonstrated with an electroplated aluminum front electrode. However, the high-resistivity silicon substrate requires a nickel seed layer to facilitate aluminum electroplating on it. In this talk, we report light-induced plating of aluminum directly on the n side of a silicon p-n junction in an ionic liquid. Without any seed layer, the deposited aluminum has good adhesion to the silicon surface. The resistivity of the aluminum deposits is as low as 4×10–6 Ω-cm, which is only about 1.5 times that of bulk aluminum. The suitable wavelength for the light source is between 600 nm to 1,000 nm. The effect of plating temperature on morphology of the aluminum deposits is analyzed. Our light-induced aluminum plating process enables simpler, lower-cost metallization on silicon solar cells than the copper plating process.

Bio-oil Production from Ablative Pyrolysis of Corncob Pellets in a Rotating Blade Reactor

Fast pyrolysis serves as an alternative and eco-friendly method to convert biomass into valuable bio-oil and char. Bio-oil is a potential source for generating renewable biofuels. In this study, corncob pellets were pyrolysed in a laboratory rotating blade ablative pyrolysis reactor. Effects of plate temperature (450 – 550°C) and nitrogen flowrate (5 – 15 L/min) were investigated on pyrolysis product yields at a fixed rotating speed of 6 Hz. Temperature and inert gas flowrate were shown to affect product distribution and yields. Maximum bio-oil yields of almost 50% w/w on dry basis were obtained at 550°C and flowrate of 5 L/min. Composition of the bio-oil contained predominantly oxygenated hydrocarbons. From analysis of chemical and physical properties, the bio-oil derived from corncob pellets showed good fuel quality, comparable to those bio-oils reported in the literature.

Communication—Light-Induced Plating of Aluminum on Silicon in a Lewis Acidic Chloroaluminate Ionic Liquid

Conventional electroplating of aluminum on silicon often requires a seed layer to overcome the high resistivity of the substrate. In this paper, light-induced plating of aluminum directly on a silicon substrate in an ionic liquid is reported. Without any seed layer, the deposited aluminum has good adhesion to the silicon surface. The resistivity of the aluminum deposits is as low as 4 × 10−6 Ω-cm, which is only about 1.5 times that of bulk aluminum. The suitable wavelength for the light source is 600 nm to 1,000 nm. The effect of plating temperature on morphology of the aluminum deposits is analyzed.

Effect of plating temperature on electroless amorphous Ni\u2013P film on Si wafers in an alkaline bath solution

Nickel–phosphorus (Ni–P) film was deposited by electroless process on the surface of p-type polycrystalline silicon at the temperature of 60–80 °C and pH value of 10.0. The effect of plating temperature on morphology, crystallographic structure, chemical composition and deposition rate of Ni–P film was studied. Microstructure and morphology of surface and cross section of the film were examined by a scanning electron microscopy and optical microscopy. The crystallographic structure and chemical composition of the film were determined by X-ray diffraction and energy dispersive spectroscopy, respectively. The results show that electroless Ni–P films were composed of the amorphous phase. The stable value P-content of the film was maintained at about 12 wt% with increasing bath temperature. The film surface was dense, and no cracking was found at 60 and 80 °C. However, the film deposited at 70 and 80 °C had a poor adherence to the substrate with evidence of delamination. The deposition rate of the film was increased with increasing plating temperature. At the same time, the deposition mechanism of the film on silicon substrate in the alkaline bath solution was addressed.

电池板温度及辐射量对光伏发电量影响的趋势面分析

利用临沂巨皇光伏跟踪示范电站2011年光伏发电数据和同步辐射观测资料，采用趋势面分析法进行春、夏、秋、冬四季和全年多晶硅太阳能板温度变化和辐射量变化对发电量影响分析，结果表明：四季和全年发电量二次和三次趋势面拟合度均达显著水平，可以揭示其影响变化趋势，电池板温度和辐射量变化对光伏发电量影响的二次趋势面拟合方程完全可以用于光伏电站发电量的预报预测。另外研究发现板温和辐射量变化对发电量的影响较为复杂，二者相互制约又共同发挥作用，总体表现出双向渐变趋势，即辐射量正向变化、板温负向变化。不同季节发电量受板温和辐射量变化影响其变化趋势和幅度也有所不同，板温对光伏发电量的影响较为复杂。 Using PV data from Linyi Juhuang PV tracking demonstration power plant in 2011 and observational data of synchrotron radiation, and adopting trend-surface analysis, this paper analyzes effect of temperature changes of polycrystalline silicon solar panels and radiation changes of four seasons as spring, summer, autumn and winter and a whole year on generating capacity. The results show that the second and third trend-surfaces fit degrees of four seasons and a whole-year generating capacity reaches significant level. The effect changing trends can be revealed. The second trend-surface fitting equation of effect of temperature of the battery plate and radiation changes on PV generating capacity can be used in forecast of PV power station output. In addition, the study finds that the effect of plate temperature and radiation changes on generating capacity is rather complex. They restrict each other and work together. In a whole, they show a bi-directional trend, that is, if radiation level has the positive change, strip temperature has the negative change. Power generations in different seasons are influenced by strip temperature and radiation changes, and the change trend and range are different. The influence of strip temperature on PV generating capacity is more complex.

Theoretical and Experimental Analysis of Flat Plate Collector

In this work a flat plate collector was designed and manufactured with dimension of (100cm×160cm×20cm) and analyzed experimentally and theoretically. The designed FPC consist of Nine pipes with (2.223cm in diameter with 140cm long) welded above the plate to act as heat removal fluid passage ways. The flow inside the pipes can takes place by forced convection. However, certain energy absorbed by the plate is lost to atmosphere due to higher temperature of the plate. Effect of plate temperature on efficiency and top loss coefficient studied for different wind velocities and different air temperature. Effect of emissivity of absorber plate on top loss coefficient was estimated.The obtained result showed that the efficiency of FPC increase by 3%with the increase in ambient temperature by8 ̊C, the efficiency decrease with the increase in plate temperature and the top loss coefficient increase when the emissivity of absorber plate increase and when wind velocity increase. The comparison of result showed a good agreement.

Sensitivity analysis of plating conditions on mechanical properties of thin film for MEMS applications

In this paper, we report the detailed investigation into the effects of plating temperature and applied current density upon the mechanical properties of plated nickel film such as Young’s modulus and residual stresses. This method uses the resonance method of atomic force microscope, which does not require specially microfabricated cantilevers and additional experimental set-up. Thin layers of nickel are electroplated onto the tip surface of AFM cantilevers and plating thicknesses were measured at the end of each plating step. The self-deformation of the released AFM cantilever is also measured as a function of the plated nickel thickness, which is converted into the quantitative residual stress by appropriate mechanics. The measured Young’s modulus is as high as that of bulk nickel at low plating temperature and at low applied current density, but drastically drops at high temperature or current density. The dependence of Young’s modulus on the plating thickness is negligible in thin film less than few microns. The residual stress is also a strong function of the process conditions, and decreased with the elevation of the current density and plating temperature. And the intrinsic and extrinsic stresses of plated nickel are separated from the measured residual stress, and correlated with plating conditions. Dependence of the plated thickness on Young’s modulus and residual stress is also considered.

The Influence of Plating Temperature on the Properties of Electroless Ni-Cu-P Alloys on Aluminum

In this work, the effect of plating temperature on the electroless plating rate and the properties of the electroless Ni-Cu-P deposits was studied. The corrosion resistance, hardness, surface morphology and components of the coating were studied by using electrochemical workstation, digital micro-hardness SEM and EDS. The results show that the optimum plating temperature is 75°C. The deposition rate, hardness and corrosion resistance are all good when the optimal temperature is 75°C. The adhesion between the deposits and the matrix is better. The deposits is smooth and uniformity, smooth by SEM. The deposit contains Ni 77.80%, Cu 7.68%, P 14.52% by the analyses of energy disperse X-ray.

Effects of plate temperature on heat transfer and emissions of impinging flames

Experiments were conducted to investigate the heat transfer and CO/NO X emissions of a premixed LPG/air circular flame jet impinging upwards normally to a flat rectangular plate. Temperatures of the impingement plate were controlled by cooling water at 38 °C, 58 °C and 78 °C which was circulating at its back in order to create different plate temperatures. Under each plate temperature, the effects of Reynolds number ( Re), equivalence ratio ( Ф) and nozzle-to-plate distance ( H) on the heat transfer and CO/NO X emissions were examined. The Re was selected to be 500, 1000 and 1500 to ensure laminar flame jets. The values of Ф were chosen to cover fuel-lean, stoichiometric and fuel-rich conditions. The H varied from 3 d to 7 d with an interval of 1 d. The flame-side temperature of the impingement plate is enhanced when the cooling water temperature increases, but the temperature difference across the impingement plate is reduced. Heat transfer from the flame to the plate is suppressed at higher cooling water temperature. The heat transfer rate is the highest when the cooling water temperature is at 38 °C and the lowest heat flux is obtained at 78 °C. At the highest cooling water temperature of 78 °C, the CO emission is reduced whereas the NO X emission is enhanced. However, this trend is reversed at the lowest cooling water temperature of 38 °C.

Effect of plating temperature on Sn surface morphology

The present study documents the effect of electroplating bath temperature on the surface brightness/reflectivity and the evolution of surface morphology of electrodeposited pure Sn films, and its subsequent effect on whisker formation. The brightness/reflectivity of the films increased with increase in temperature. Detailed microstructural analysis of the electroplated Sn films showed that unique pyramid shaped features formed at elevated temperatures (below 85 °C) and the underlying surface became increasingly smooth with temperature. The plating temperature also affected the morphology of the whiskers that formed upon aging at room temperature. The whisker diameter increased whereas the size decreased with increase in plating temperature. It was also observed that the diameter and length of each whisker depend on the Sn grain size.

Mismatch Strain and Residual Stress of Freestanding Electroplated Ni Thin Film

In this paper, we report the detailed investigation into the effects of plating temperature and applied current density upon the residual stress of plated nickel film. Thin layers of nickel are electroplated onto the tip surface of atomic force microscope (AFM) cantilevers and quantitative residual stress of plated nickel film is determined by detecting the self-deformation of the released AFM cantilever. The residual stress was a strong function of the process conditions, and decreased with the elevation of the current density and plating temperature. And the intrinsic and extrinsic stresses of plated nickel are separated from the measured residual stress, and correlated with plating conditions. Dependence of the plated thickness on the residual stress is also considered. Through-thickness variation of residual stress is also experimentally investigated and compared to the analytical values.

TEMPERATURE DEPENDENCE OF ELECTROLESS Ni–P DEPOSITION ON POLYESTER FABRIC

The effects of plating temperature on the plating rate, P content, surface morphology, and electrical resistance of the electroless Ni–P deposits were studied. The results showed that the deposition rate of the Ni–P deposit and P content of the Ni–P layer increased with the rise of temperature of the plating bath. Scanning electron microscopy of the Ni–P deposits showed a nodule structure. The Ni–P plating layers had an amorphous structure and surface resistance of the layer decreased with the rise of temperature. In addition, the electromagnetic interference shielding effectiveness (EMI SE) of electroless Ni–P plated polyester fabric was also investigated. The result indicated that EMI SE of Ni–P plated polyester fabric was close to 45–50 dB when the surface resistance was 0.63 Ω/□.

Microstructure and electromagnetic interference shielding effectiveness of electroless Ni–P plated polyester fabric

Microstructure and electromagnetic interference shielding effectiveness of electroless Ni–P deposits obtained from an alkaline hypophosphite reducing electroless nickel bath was studied. The effects of plating temperature on the deposition rate, surface morphology, chemical composition and structure of the electroless Ni–P deposits were investigated. Surface resistance and electromagnetic interference (EMI) shielding effectiveness (SE) of Ni–P plated polyester fabric were also evaluated. The results demonstrated electroless Ni–P plated polyester fabric present useful EMI shielding materials.

The effect of plate temperature on the onset of wetting

The wetting front velocity of a thin liquid film flowing over a hot flat plate is investigated analytically. An exact solution is developed as a function of the Peclet number, the Jakob number, the Biot number, the heat capacity ratio, and the thickness ratio of plate and liquid film. The initial plate temperature affects only the time required for the onset of wetting, and the actual wetting front velocity is independent of the initial plate temperature. The experimental data obtained by other investigators are used to compute the onset time and actual wetting front velocity. The results provide further insight into the mechanism and help to clarify the fundamental phenomena.

ホウ水素化ナトリウムによる還元ニッケル膜のメッキ温度の影響と成長機構

Effects of plating temperature and growth mechanism on reduced Ni films were studied by electron microscopy. The shape of nebulous crystals and their arrangement of crystal orientation were not changed, even if the plating temperature fell from 91 to 60°C; and they were also independent of decrease in quantity of reducing agent in the plating bath or increase in thickness of film. The growth process of reduced Ni films was as follows; in the earlier stage, small nuclear nebulous crystals deposited on the substrate by initiation treatment followed by two dimensional growth of nebulous crystals at this site, which gradually covered the whole surface of substrate. At this stage, the secondary nucleation did not occur on the other surface of the substrate. The nebulous crystals grown in two dimensions on the surface of substrate accepted Ni adatoms only in its growth direction, and these adatoms were crystallized in nebulous crystals at this site. The growth direction of nebulous crystals was independent of the crystal orientation of substrate. The increase in thickness of the plating film depended on agitation and thermal convection of the plating bath.