Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
The effect of quenching from different temperatures on Bi 0.88 Sb 0.12 alloy  [PDF]
K. Malik,Diptasikha Das,S. K. Neogi,A. K. Deb,Arup Dasgupta,S. Bandyopadhyay,Aritra Banerjee
Physics , 2015, DOI: 10.1016/j.jpcs.2015.11.017
Abstract: Structural, thermal, resistive and magnetic properties of melt quenched Bi 0.88 Sb 0.12 alloys are reported. The samples are heated at three different temperatures, followed by rapid quenching in liquid nitrogen. Large temperature difference between liquidus and solidus lines, led to microscopic in-homogeneity in the alloy. The effect of quenching from different temperatures in polycrystalline Bi 0.88 Sb 0.12 alloy has been studied. The parameters such as strain, unit cell volume, and resistivity are found to increase with temperature. Thermal variation of resistivity depicts non monotonic temperature dependence. The total negative susceptibility increases and band gap of semiconducting Bi 0.88 Sb 0.12 samples decreases with increasing temperature.
G.R. Li
,Y.X. Tong and G.K. Liu School of Chemistry and Chemical Engineering,Zhongshan University,Guangzhou,China

金属学报(英文版) , 2003,
Abstract: The cyclic voltametry and potentiostatic electrolysis was used to investigate the preparation of Bi-Fe alloy films in LiClO4-DMSO (dimethylsulfoxide) system. The effects of several factors including the potential of deposition, current density and concentration of iron and bismuth in the solution on the Fe content in the alloy deposits were studied. Experimental results indicated that the amorphous alloy films of Bi-Fe containing Fe 4.40wt%-33. 67wt% could be prepared by controlling the system composition and deposition conditions. They were gray, uniform, metallic luster and adhered firmly to the copper substrates analyzed by EDS, SEM and XRD. After heat treatment of crystallization at 270℃ for 1h, the crystal phase of Bi-Fe can be found in XRD patterns.
The mechanism of the influence of Bi(or Sb) and rare earth on high temperature performance of AZ91 magnesium alloy

Zhang Guo-Ying,Zhang Hui,Wei Dan,Luo Zhi-Cheng,Li Yu-Cai,

物理学报 , 2009,
Abstract: 利用大角重位点阵概念建立了AZ91镁合金基体(α相)和镁[0001]对称倾斜晶界原子结构模型,应用实空间的连分数方法计算了体系的结构能,环境敏感镶嵌能以及相互作用能.结果发现,在镁合金基体中,Al和稀土形成团簇时比较稳定,Al,Bi或Sb与稀土形成团簇时不稳定.Bi或Sb和稀土元素同时存在于AZ91镁合金中时,一方面Bi或Sb将可与RE结合形成RE2Bi(RE2Sb)或RE-Bi(RE-Sb)化合物弥散分布于晶界,另一方面镁合金基体中会形成Al11
A study on the mechanism of the influence of Bi, Sb alloying on microstructure and properties of AZ91 magnesium alloy

Zhang Guo-Ying,Zhang Hui,Fang Ge-Liang,Li Yu-Cai,
,张 辉,方戈亮,李昱材

物理学报 , 2005,
Abstract: 利用大角重位点阵模型建立了AZ91镁合金α相[0001]对称倾斜晶界原子结构模型,应用实空间的连分数方法计算了Mg合金的总结构能,合金元素引起的环境敏感镶嵌能及原子间相互作用能,讨论了主要合金元素Al及Bi,Sb在AZ91中的合金化行为.计算结果表明,Al,Bi,Sb固溶于α相内或晶界区使总结构能都降低,起到固溶强化作用;合金元素在AZ91α相内趋于均匀分布,在晶界区易占位于三角椎上部.AZ91镁合金中加入Bi或Sb时,Bi或Sb比Al容易偏聚于晶界,从而抑制了Al在晶界的偏聚,促进基体中连续的Mg17Al12相的析出,提高AZ91合金室温性能; AZ91合金中(α相内和晶界区)主要合金元素Al和微加元素Bi,Sb都能够形成有序相Mg17Al12,Mg3Bi2或Mg3Sb2,且在晶界区形成的量大.Bi,Sb加入AZ91合金中,由于Bi,Sb抑制Al在晶界的偏聚,晶界区主要析出相为Mg3Bi2或Mg3Sb2,提高镁合金高温性能.
Anomalous and normal dependence of the sound velocity in the liquid Bi-Sb system  [PDF]
Moran Emuna,Yaron Greenberg,Eyal Yahel,Guy Makov
Physics , 2014, DOI: 10.1016/j.jnoncrysol.2012.11.007
Abstract: The sound velocity in selected liquid alloys of the isomorphous Bi-Sb system was measured as a function of temperature to a high accuracy of 0.2%. The sound velocity temperature coefficient, dlnc/dT, at the liquidus is found to vary non-monotonously as a function of alloy composition, with the transition from normal to anomalous temperature dependence occurring at a composition of approximately Bi35Sb65. Beyond this composition up to approximately Bi10Sb90 the sound velocity is found to be temperature independent over a wide range. The deviation of the sound velocity from that expected in an ideal solution is found to be dominated by a sub-regular interaction. The present measurements allow the determination of the pressure dependence of the sub-regular solution interaction parameters and are found to be consistent with high pressure studies of the phase diagram in this system. The sound velocity is shown to be an effective measure of the pressure dependence of the alloy interactions.
Hydrogen Evolution Reaction on Amorphous Ni-P Electrodes Produced by Electrodeposition

CHEN Yan-li,LI Ling-chuan,ZHANG Yi,CAO Hong-bin,

过程工程学报 , 2004,
Abstract: NiP alloy electrodes with different phosphorus contents were prepared by means of electrodeposition method. The catalyzing property of the different electrodes as the hydrogen evolution-cathode in 1 mol/L KOH solution at 20oC was studied with constant current polarization method. The structures of NiP alloy electrodes were also analyzed by XRD and SEM. The results show that the NiP alloy electrode with phosphorus content of 8.49 at% (atomic percent) performs excellent catalyzing property. Its hydrogen evolution overpotential is 95 mV, the lowest at the current density of 150 mA/cm2, which is 342 mV lower than that of Ni electrode. And its Tafel slope in the low current density is 65.4 mV/dec. This property is related to its phosphorus content and structure.
Effect of Spinning and Milling Time on Thermoelectric Properties of the p-type (Bi0.25Sb0.75)2Te3 Alloy
WANG Lei1,2, LU Qing-Mei1,2, ZHANG Xin1,2, ZHANG Jiu-Xing1,2
无机材料学报 , 2010, DOI: 10.3724/sp.j.1077.2010.00588
Abstract: A series of p type bulk (Bi0.25Sb0.75)2Te3 thermoelectric materials were prepared by melt spinning-mechanical milling (MM) and spark plasma sintering (SPS). Electrical conductivity, Seebeck coefficient and thermal conductivity of the sintered samples were measured in the temperature range from 300K to 523K. The effects of milling time on thermoelectric properties were investigated in system. The results show that, with the extension of milling time, the electrical conductivity of the sample increases and then decreases, Seebeck coefficient changes little, while the thermal conductivity decreases with the increase of milling time. As a result, the bulk milled for 20h has the highest ZT value 0.96 at room temperature, meanwhile the bending strength reaches 91MPa.
Sb concentration dependent structural and resistive properties of polycrystalline Bi-Sb alloys  [PDF]
K. Malik,Diptasikha Das,D. Mondal,D. Chattopadhyay,A. K. Deb,S. Bandyopadhyay,Aritra Banerjee
Physics , 2012, DOI: 10.1063/1.4759137
Abstract: Polycrystalline Bi-Sb alloys have been synthesized over a wide range of antimony concentration (8 at% to 20 at%) by solid state reaction method. In depth structural analysis using X-Ray diffraction (XRD) and temperature dependent resistivity measurement of synthesized samples have been performed. XRD data confirmed single phase nature of polycrystalline samples and revealed that complete solid solution is formed between bismuth and antimony. Rietveld refinement technique, utilizing MAUD software, has been used to perform detail structural analysis of the samples and lattice parameters of synthesized Bi-Sb alloys have been estimated. Lattice parameter and unit cell volume decreases monotonically with increasing antimony content. The variation of lattice parameters with antimony concentration depicts a distinct slope change beyond 12 at% Sb content sample. Band gap has been estimated from the thermal variation of resistivity data, with the 12% Sb content sample showing maximum value. It has been observed that, with increasing antimony concentration the transition from direct to indirect gap semiconductor is intimately related to the variation of the estimated lattice parameters. Band diagram for the polycrystalline Bi-Sb alloy system has also been proposed.
Effect of Antimony Additions on Corrosion and Mechanical Properties of Sn-Bi Eutectic Lead-Free Solder Alloy  [PDF]
Alberto Torres, Luis Hernández, Octavio Domínguez
Materials Sciences and Applications (MSA) , 2012, DOI: 10.4236/msa.2012.36051
Abstract: The goal of the present work is to investigate the effects of the addition of Sb (0, 3 and 6 wt%) on structure, melting, corrosion and mechanical properties of Sn-Bi eutectic solder alloys. The mechanical properties of the bulk Sn-Bi-Sb solders were higher as the amount of antimony increases, making compressive strength augment from 65 MPa to 100 MPa when 6 wt% Sb was incorporated to the Sn-Bi eutectic alloy. The three alloys presented a melting temperature that is smaller to the one exhibited by the eutectic alloy Sn-38Pb (Tm = 183°C). According to the electrochemical results, the addition of higher contents of Sb to the Sn-Bi eutectic alloy had a positive effect: it ennobled the Ecorr values.
Preparation of Ni-Co Alloy Foils by Electrodeposition  [PDF]
Yu-Yang Yang, Bin Deng
Advances in Chemical Engineering and Science (ACES) , 2011, DOI: 10.4236/aces.2011.12005
Abstract: Electrodeposition of Ni-Co alloy foils on titanium substrate was performed in an acid chloride- sulphate bath. The influences of electrodeposition parameters such as current density, temperature, pH value, cobalt sulphate and saccharin concentration on composition and current efficiency were investigated in detail. The morphology and the microstructure of deposits were analyzed by SEM and XRD, respectively. The results indicated that the optimum parameters were current density 3-4 A/dm2, pH 2-3, temperature 40-50?C, cobalt sulphate 20 g/l and saccharin 2-3 g/l. Chemical analysis of the deposits by EDS revealed anomalous Ni-Co codeposition occured in this system. The SEM showed that hydroxide particles were not present on the surface and that fine-grain, smooth and compact Ni-Co alloy deposits were obtained. The crystallographic structures of Ni-Co alloy foils were the fcc Ni solid solution. The Ni-Co alloy foils with Co content 17.3-37.2 wt% and thickness of 20-45 μm were bright with low residual stress and super toughness.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.