Microstructure Evolution of Intermetallics Produced by Laser Powder Deposition

NiAl intermetallic alloys are potential high temperaturestructural materials in aeronautical and astronauticalindustries[1].However,the poor ductility andtoughness at room temperature severely restrict theirengineering applications[2,3].It is important todevelop new technology to product intermetallicmaterials for the improvement of the comprehensiveproperties and the workability.Laser powder depositionhas been used to synthesize many new materials.Furthermore,if incorporated with rapid proto…     

X-ray fluorescence spectrometry determination of open-hearth furnace slag by pressed powder briquetting

Chemical composition of open-hearth furnace slag isimportant for the metal and casting quality. The chemicalcomponents of slag need to be analyzed precisely andaccurately.For a long time the composition determination of slag ismade chemically, which involves complicated processes,long analytical cycle, high cost and tedious work. A greatmany successful applications of ores analysis by x-rayfluorescence spectrometry (XRF) have been reported[1-4].Powder-fused wafer is a sampling method used in…     

SURFACE MODIFICATION ON STEEL BY RARE EARTH AND LASER TREATMENT

ＳＵＲＦＡＣＥＭＯＤＩＦＩＣＡＴＩＯＮＯＮＳＴＥＥＬＢＹＲＡＲＥＥＡＲＴＨＡＮＤＬＡＳＥＲＴＲＥＡＴＭＥＮＴ①ＳｈｅｎＹｉｆｕ１，２，ＦｅｎｇＺｈｏｎｇｃｈａｏ１，ＣｈｅｎＪｉｚｈｉ１，ＬｉａｎｇＹｏｎｇ１１ＩｎｓｔｉｔｕｔｅｏｆＭｅｔａｌＲｅｓｅａ...     

WELL-DISPERSED NANODIAMOND AQUEOUS SUSPENSIONS——PREPARATION,PROPERTIES AND APPLICATIONS

1　INTRODUCTIONAsitwassynthesizedundertheconditionofhightemperatureandhighpressure ,andowingtothecommoncharacteristicsoffinedimensionandhighsurfaceenergyofnanoscaledparticles ,nanodiamond (ND )preparedbydetonationexplosioncaneasilyformstrongaggregates WhenNDpowderwasaddedinaqueousmedia ,obviousaggregationandsedimentationcanbeobserved ,whichimpairsitscharacteristicsasananometerparticle ,andthushindereditsapplication Inthiscase ,stabledispersionofNDinaqueousmediaisofgreatimportance[1 4 ] …     

Effect of copper addition on the thermal contraction of indium melt clusters

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     

Press Releases for GIFA/METFC/THERMPOCESS/NEWCAST 2007

Nomen est omen: Under the motto "The Bright World of Metals"the four international technology trade fairs GIFA, METEC,THERMPROCESS and NEWCAST drew to a successful close on Saturday. Over 1 700 companies, associations and research institutes presented the latest innovations in the areas of foundry technology, castings, metallurgy and thermal process engineering in Düsseldorf.     

Discussion on compact mechanism of air-stream and synchro-formed clamp plate impact molding

1 .Introduction Due to many advantages such as simple molding machine structure high compact compaction of sand mold, speed and well-distributed the air-stream impact molding method However, has been extensively used in production.when this molding method is applied to mold complicated pattern with wider top surface and deep     

Synthesis and luminescent properties of Eu~(3+)-doped Na_(24)As_2W_(22)O_(83)

The Eu3+-doped Na24As2W22O83 phosphor has been prepared by solid state reaction from Na3AsO412H2O, Na2WO4 2H2O and WO3, and characterized by elemental analysis, infrared spectroscopy and powder X-ray diffractometry. According to the measurements with X-ray diffraction, this material belongs to orthorhombic system with its lattice constants: a = 1.4750 nm, b = 1.1944 nm, c = 1.1062 nm, it is consistent with space group D24-P212121 (No.19). The emission and excitation spectra were measured. The luminescent properties of Eu3+-doped Na24As2W22O83 and mechanism of energy transfer were discussed.     

Lower estimation of approximation rate for neural networks

Let SFd and Πψ,n,d = { nj=1bjψ(ωj·x+θj) :bj,θj∈R,ωj∈Rd} be the set of periodic and Lebesgue’s square-integrable functions and the set of feedforward neural network (FNN) functions, respectively. Denote by dist (SF d, Πψ,n,d) the deviation of the set SF d from the set Πψ,n,d. A main purpose of this paper is to estimate the deviation. In particular, based on the Fourier transforms and the theory of approximation, a lower estimation for dist (SFd, Πψ,n,d) is proved. That is, dist(SF d, Πψ,n,d) (nlogC2n)1/2 . T...     

考虑源荷侧灵活性资源的风光消纳互动调控

针对大规模新能源并网导致电网调控的灵活性不足问题,考虑电网灵活性供需平衡,提出灵活性资源（FR）参与风光消纳的互动调控方法,建立规划—运行双层模型对风光消纳进行调控优化。规划层考虑FR改造成本与电压稳定性初步分配新能源安装位置与灵活性资源改造容量,运行层综合经济成本、灵活性缺失度及峰谷差值等指标协同调控源荷资源,通过混合种群迁徙算法进行多目标优化,筛选求解后的多样性方案反馈规划层,得到最优调控结果。最后,结合东北某实际电网进行仿真分析,结果表明合理配置多元化FR能改善电网的风光消纳能力及其调控灵活性,验证了所提方法的合理性和有效性。