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Intermetallic Compounds (intermetallic + compound)
Selected AbstractsThe Effect of Intermetallic Compound on Shear Strength of Diffusion Soldered InterconnectionADVANCED ENGINEERING MATERIALS, Issue 3 2006J. Wojewoda The mechanical properties of diffusion soldered Cu/Cu interconnections were examined. Application of the indium-tin eutectic alloy as a solder material and different manufacturing temperatures resulted in creation of the intermetallics in the interconnection area. The calculated cross-sections of the Cu-In-Sn diagram combined with Scanning Electron Microscopy investigation allowed for the detailed description of the joints before the shear test and after it. [source] The Bonding of Interstitial Hydrogen in the NiTi Intermetallic CompoundCHEMINFORM, Issue 11 2007Dae-Bok Kang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] ChemInform Abstract: Synthesis and Structural Characterization of A3In2Ge4 and A5In3Ge6 (A: Ca, Sr, Eu, Yb) , New Intermetallic Compounds with Complex Structures, Exhibiting Ge,Ge and In,In Bonding.CHEMINFORM, Issue 35 2010Tae-Soo You Abstract The title compounds are prepared from mixtures of the elements using excess In as a flux (alumina crucible, 1223 K, 10,12 h) and characterized by powder and single crystal XRD, and TB-LMTO electronic structure calculations. [source] ChemInform Abstract: Crystal Structure and Magnetic Properties of Novel Intermetallic Compounds in the Er,Cu,Ga System.CHEMINFORM, Issue 35 2009B. Belgacem Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Intermetallic Compounds with 1D Infinite Tunnels.CHEMINFORM, Issue 51 2006Structures of AAu4In2 (A: K, Syntheses Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] New Intermetallic Compounds in the Ln,Zn,Al Systems and Their Crystal Structure.CHEMINFORM, Issue 39 2005B. Stel'makhovych Abstract For Abstract see ChemInform Abstract in Full Text. [source] Low-Temperature Polyol Synthesis of AuCuSn2 and AuNiSn2: Using Solution Chemistry to Access Ternary Intermetallic Compounds as Nanocrystals.CHEMINFORM, Issue 36 2005Brian M. Leonard Abstract For Abstract see ChemInform Abstract in Full Text. [source] Ab initio Study of the Electronic Structure of Rhodium Based Intermetallic Compounds under PressureCHEMINFORM, Issue 46 2004M. Rajagopalan Abstract For Abstract see ChemInform Abstract in Full Text. [source] Ln2Sn3 (Ln: La,Nd, Sm): A Family of Intermetallic Compounds with Their Own Triclinic Structure.CHEMINFORM, Issue 38 2003Maria L. Fornasini Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: The Electronic Structure of the YNi5, YNi4Al and YNi3Al2 Intermetallic Compounds and Their Model MonohydridesCHEMINFORM, Issue 17 2002G. I. Miletic Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Formation of diffusion-hindering interlayers in metals in contact by dedicated thermal treatmentCRYSTAL RESEARCH AND TECHNOLOGY, Issue 1-2 2005D. C. Meyer Abstract Thermal evolution of the structure of Fe/Al multilayers (MLs) with nominal composition 5*(5 nm Al / 5 nm Fe) prepared by crossed-beam pulsed laser deposition is studied by wide-angle X-ray scattering and X-ray reflectometry after different temperature-time procedures of thermal treatments under high-vacuum conditions. In comparison to direct thermal annealing at temperatures of 250 °C and 275 °C, respectively, which results in nearly complete mixing of the MLs and formation of the FeAl intermetallic compound, quite different behaviour was found after dedicated thermal pretreatment. Annealing at successive growing temperatures before final annealing at temperatures mentioned, resulted in conservation of pronounced multilayer structure. From the results it is generalised, that also in the case of ML systems, the tendency of mixing a dedicated tuning of interface characteristics by thermal treatment allows for formation of diffusion-hindering interlayers. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Study of corrosion resistance improvement by metallic coating for overhead transmission line conductorELECTRICAL ENGINEERING IN JAPAN, Issue 1 2008Masanori Isozaki Abstract Applying anticorrosion grease and aluminum-clad steel (AC) wires to ACSR have been adopted as general methods to protect overhead transmission line conductors and/or wires from corrosion. However, in some cases those means have been found to be ineffective on some transmission lines passing through acid atmosphere in the vicinity of a factory exhausting acid smoke. The corrosion caused by acid atmosphere is characterized by a higher speed in its progress as is well known. As means against such acid corrosion, application of high-purity aluminum, selective removal of intermetallic compound in aluminum, and plastic coating wires have been reported before, and each has both advantages and disadvantages. In a former report, we found that a new type of anticorrosion grease shows an excellent property against acid atmosphere as well as in a salty condition. Here we present a new type of anticorrosion technology of applying high-corrosion-resistance aluminum alloy or zinc coatings on each component wire of a conductor that we succeeded in developing through a serial study of anticorrosion methods on overhead transmission lines. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(1): 41,47, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20365 [source] Structures of stable and metastable Ge2Bi2Te5, an intermetallic compound in a GeTe,Bi2Te3 pseudobinary systemACTA CRYSTALLOGRAPHICA SECTION B, Issue 3 2007Toshiyuki Matsunaga Ge2Bi2Te5 in the GeTe,Bi2Te3 pseudobinary system has two single-crystalline phases: a metastable phase with an NaCl-type structure and a stable phase with a nine-layer trigonal structure. In the metastable phase, the structure consists, in the hexagonal notation, of infinitely alternating stacks of Te and Ge/Bi layers at equal intervals along the c axis. On the other hand, in the stable phase those two layers are stacked alternately nine times to form an NaCl block. The blocks are then piled to construct a nine-layered trigonal structure with cubic close-packed stacking. Both ends of each block are covered with Te layers, contrary to the infinite alternation of Ge/Bi and Te layers in the structure of the metastable phase. The Ge/Bi layers in the metastable phase contain as much as 20,at.,% vacancies; on the other hand, those in the stable phase are filled with atoms. These two crystalline phases in Ge2Bi2Te5 have identical atomic configurations to the two corresponding phases found in Ge2Sb2Te5. [source] Working Electrodes from Amalgam Paste for Electrochemical MeasurementsELECTROANALYSIS, Issue 4 2008Bogdan Yosypchuk Abstract Paste electrode with paste amalgam as an active electrode material is described here for the first time. Designed electrode from silver paste amalgam (AgA-PE) is solely metallic and does not contain any organic binder. Mechanical surface regeneration of AgA-PE is performed in the same way as for classical carbon paste electrodes and reproducibility of such regeneration is about 10%. Electrochemical surface regeneration appeared very efficient for most measurements. In dependence on paste metal content, the electrode surface can be liquid (resembling a film) or rather solid. The hydrogen overvoltage on AgA-PE is high, and the electrode allows measurements at highly negative potentials. AgA-PE is well suited for study of reduction or oxidation processes without an accumulation step. Anodic stripping voltammetry of some metals tested on the electrode is influenced by formation of intermetallic compounds. The measurement based on cathodic stripping voltammetry (adenine, cysteine) and on catalytic processes from adsorbed state (complex of osmium tetroxide with 2,2,-bipyridine) can be performed on AgA-PE practically under the same conditions as found earlier for HMDE and for silver solid amalgam electrode. The working electrode from paste amalgam combines the advantages of paste and metal electrodes. [source] Manufacturing of Net-Shape Reaction-Bonded Ceramic Microparts by Low-Pressure Injection Molding,ADVANCED ENGINEERING MATERIALS, Issue 5 2009Nadja Schlechtriemen Reaction-bonded oxide ceramics based on intermetallic compounds are able to compensate the sintering shrinkage completely due to their high increase in volume caused by oxidation. Using low-pressure injection molding (LPIM) for shaping ceramics avoids needless materials loss and affords the manufacturing of complex formed structures. The combination of both, reaction-bonded ceramic and LPIM-processing, offers the manufacturing of ceramic microparts by keeping a high accuracy and replication quality. [source] Effects of Zirconium Additions on the Microstructure of As-Cast and Aged AZ91 Magnesium AlloyADVANCED ENGINEERING MATERIALS, Issue 3 2009Farhoud Kabirian The effects of Zr addition on the microstructure of AZ91 alloy were investigated under as-cast and isothermally aged conditions. The microstructures contained a eutectic , -Mg17Al12 phase together with fine Al,Zr intermetallic compounds. These intermetallic compounds inhibited grain growth during the 420,°C isothermal aging of Zr-containing alloys. Microstructural changes caused by Zr additions were most probably due to the consumption of Al by Zr, and redistribution of Al during solidification of dendrites. [source] Anisotropic diffraction peak broadening and dislocation substructure in hydrogen-cycled LaNi5 and substitutional derivativesJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2000Anisotropic peak broadening in hydrogen-cycled hexagonal LaNi5 and substitutional derivatives has been studied by means of synchrotron powder diffraction. The data have been analysed by a local lattice parameter variation method implemented in a Rietveld code and by an individual profile fitting using a dislocation peak broadening model. Two main dislocation systems, both with Burgers vector 1/3,110,, are activated by misfit of the lattice parameters between the intermetallic compounds and their hydrides. Two types of diffraction peak broadening effect were observed as a function of the substitution in LaNi5: (i) a decrease or disappearance of the broadening related to the decrease of the total dislocation density and (ii) a change in the anisotropy of the broadening related to the change of the nature of the dislocation system involved. The latter effect was attributed to a change in shape of the hydride precipitates. [source] Electrochemical and mechanical behaviour of Sn-2.5Ag-0.5Cu and Sn-48Bi-2Zn soldersMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 8 2008G. Montesperelli Abstract In this paper, two tin-based alloys (Sn-2.5Ag-0.5Cu and Sn-48Bi-2Zn) are proposed as new lead-free solders. Alloys have been developed by melting pure elements. Samples have been evaluated in terms of microstructure, corrosion resistance and mechanical features. Corrosion tests have been performed in 3% NaCl solution by polarization curves and electrochemical impedance spectroscopy (EIS). SEM observations and EDS analysis were carried out on samples before and after corrosion tests. Static monotonic tensile tests have been performed on three specimens for each alloy. SEM and EDS analysis revealed the presence of Sn-Ag and Sn-Cu intermetallic compounds within the Sn-Ag-Cu alloy. As a result of corrosion test, the Sn-Ag-Cu alloy showed a better corrosion resistance with respect to Sn-Bi-Zn. Both alloys evidenced good mechanical properties higher than the traditional Sn-Pb system. Sn-Ag-Cu seems to be a suitable soldering material. [source] Beurteilung von Loten und Lötverbindungen unter dem Einfluss steigender Kupfergehalte in verunreinigten bleifreien LotbädernMATERIALWISSENSCHAFT UND WERKSTOFFTECHNIK, Issue 1 2008B. Wielage Lead-free solders; phase selection; deep-etching; intermetallic compounds Abstract Zuverlässigkeit und Degradationsverhalten bleifreier Lote sind aufgrund von Widersprüchlichkeiten und notwendiger Problemlösungen nach wie vor Aspekte weiterer Untersuchungen. Die vorliegende Arbeit zeigt anhand von Phasenselektion der intermetallischen Phasen Ag3Sn und Cu6Sn5 sowie (Cu,Ni)6Sn5 und (Ni,Cu)3Sn4 morphologisch-mikrostrukturelle Zusammenhänge in Verbindung mit mechanischen Eigenschaften auf. Dazu wurden insbesondere das metallografische Tiefätzen und die instrumentierte Eindringprüfung genutzt. Die Lotlegierungen SnAg3,8CuX und SnCuXNi0,07 und deren Lötverbindungen wurden durch verschiedene Methoden komplex evaluiert. Es konnte nachgewiesen werden, dass das Zulegieren von Nickel als degradationsvermindernde Maßnahme des Kupfer-Leachings zur Versprödung der Legierung durch das Wachstum der Phase (Cu,Ni)6Sn5 führen kann. Evaluation of solders and solder joints processed in lead free solder baths with increasing copper content Reliability and degradation behavior of lead-free solders are due to contradictions and necessary problem solving remaining aspects of further investigations. This paper shows morphologic and microstructural relationships in conjunction with mechanical properties on the intermetallic phases Ag3Sn and Cu6Sn5 as well as (Cu, Ni)6Sn5 and (Ni, Cu)3Sn4. In particular, the methods of metallographic deep-etching and the instrumented indentation hardness test were applied. The solders SnAg3,8CuX and SnCuXNi0,07 and their solder joints were comprehensively evaluated by various methods. It has been shown that alloying with nickel as a method of decreasing copper-leaching can induce embrittlement by growth of the (Cu,Ni)6Sn5 phase. [source] HRTEM of dislocation cores and thin-foil effects in metals and intermetallic compoundsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 5 2006M.J. Mills Abstract Examples of the observation and analysis of dislocation cores and dislocation fine structure in metals and intermetallics using high resolution transmission electron microscopy are discussed. Specific examples include the 60° dislocations in aluminum, a,011, edge dislocations in NiAl, and screw dislocations in Ni3Al. The effect of the thin TEM foils on the structure and imaging of these dislocations is discussed in light of embedded atom method calculations for several configurations and coupled with image simulations. Some generalizations based on these calculations are discussed. These analyses enables determination of the spreading or decomposition of the edge component of the cores, both in and out of the glide plane, which can have significant implications for the modeling of macroscopic behavior. Microsc. Res. Tech. 69:317,329, 2006. © 2006 Wiley-Liss, Inc. [source] Antiferromagnetic-to-ferromagnetic transition induced by aluminum in the Ti(Fe1,xAlx)2 intermetallic compounds: a 57Fe Mössbauer spectroscopy studyPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 10 2007N. N. Delyagin Abstract Mössbauer spectroscopy has been used to investigate the hyperfine field distributions and the local spin configurations of Fe atoms in the magnetically ordered Ti(Fe1,xAlx)2 compounds. The evolution of the spin arrangement of the Fe atoms was observed over the concentration range 0 , x , 0.25 at 5 K. The Al impurity suppresses the ferromagnetic exchange in the Fe(6h) layers and simultaneously provides the conditions for a transition of the Fe(2a) atoms, which are nonmagnetic in the TiFe2 compound, to the states with nonzero magnetic moment. The magnetic behavior of the Fe(2a) atoms is the key factor governing the anti- to ferromagnetic transition in the Ti(Fe1,xAlx)2 compounds. The magnetic ordering temperatures of the Ti(Fe1,xAlx)2 compounds were determined. In addition, the parameters of the electric-field gradient in TiFe2 as well as the relationship between the value of the magnetic moment of the Fe atom and the type of atomic configuration were discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] A single law for the activation energies of self-diffusion of various cubic metals, intermetallic compounds, ionic crystals and oxidesPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 4 2007Hans Siethoff Abstract In previous publications the author put forward a relation which, for face-centred cubic metals and intermetallic compounds with B2 and L12 structures, connected the activation energy of self-diffusion with lattice constant and shear modulus. It is one aim of the present study to show that this formalism can be extended to intermetallic compounds with C1, D03 and C15 crystal structures. Since the covalently bonded cubic semiconductors and ceramics obey a different law, the question concerning the influence of the chemical bond was additionally investigated. Therefore ionic crystals and oxides with B1, B2 and C1 structures were analysed. It is demonstrated that these materials obey the same law as the metals and intermetallic compounds, for the B1 structure, however, the prefactor of the common rule is different. To be able to evaluate such differences, the proposed relation had to be more quantitatively derived than it was done before. Some cubic transition metals do not fit in the general picture. The deviations are traced back to the binding properties of the electronic d-bands. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Structural investigation of GeSb6Te10 and GeBi6Te10 intermetallic compounds in the chalcogenide homologous seriesACTA CRYSTALLOGRAPHICA SECTION B, Issue 4 2010Toshiyuki Matsunaga The crystal structures of GeSb6Te10 and GeBi6Te10 were scrutinized using an X-ray powder diffraction method, which revealed that these compounds crystallize in trigonally distorted cubic close-packed structures with a 51-layer period (). Each layer consists of a triangular atomic net; Te atoms occupy their own specific layers, whereas Ge, Sb and Bi atoms are located in the other layers. In these pseudobinary compounds, random atomic occupations of Ge and Sb/Bi are observed and the layers form two kinds of elemental structural blocks by their successive stacking along the c axis. These compounds can be presumed to be isostructural. It is known that the chemical formula of the chalcogenide compounds with the homologous structures found in these pseudobinary systems can be written as (GeTe)n(Sb2Te3)m or (GeTe)n(Bi2Te3)m (n, m: integer); the GeSb6Te10 and GeBi6Te10 investigated in this study, which correspond to the case in which n = 1 and m = 3, naturally have 3,×,l = 51-layer structures according to a formation rule l = 2n + 5m commonly found in the compounds of these chalcogenide systems (l represents the number of layers in the basic structural unit). Calculations based on the density functional theory revealed that these materials are compound semiconductors with very narrow band gaps. [source] The self-hosting structure of ,-TaACTA CRYSTALLOGRAPHICA SECTION B, Issue 1 2002Alla Arakcheeva Using electrodeposition from a bath of molten fluorides, single crystals of tetragonal ,-tantalum have been obtained for the first time at normal pressure. The unit-cell parameters are a = 10.211,(3), c = 5.3064,(10),Å, space group P21m. The ,-Ta structure belongs to the ,-type Frank,Kasper structures which are typical for binary intermetallic compounds and ,-U. In comparison to the ,-type, additional intercalated Ta atoms (population factor ,0.01) have been detected between the atoms located in the channels of the structure. The shorter interatomic distances observed between the channel atoms in comparison with the atoms of the framework justify the `self-hosting' characteristic. ,-Ta exhibits common features with the complex tetragonal structures of the high-pressure phases for the elements Rb, Ba, Sr, Bi and Sb. [source] Intermetallics as Zintl Phases: Yb2Ga4Ge6 and RE3Ga4Ge6 (RE=Yb, Eu): Structural Response of a [Ga4Ge6]4, Framework to Reduction by Two ElectronsCHEMISTRY - A EUROPEAN JOURNAL, Issue 13 2004Marina A. Zhuravleva Abstract Two new intermetallic compounds, Yb2Ga4Ge6 and Yb3Ga4Ge6, were obtained from reactions in molten Ga. A third compound, Eu3Ga4Ge6, was produced by direct combination of the elements. The crystal structures of these compounds were studied by single-crystal X-ray diffraction. Yb2Ga4Ge6 crystallizes in an orthorhombic cell with a=4.1698(7), b=23.254(4), c=10.7299(18) Å in the polar space group Cmc21. The structure of RE3Ga4Ge6 is monoclinic, space group C2/m, with cell parameters a=23.941(6), b=4.1928(11), c=10.918(3) Å, ,=91.426(4)° for RE=Yb, and a=24.136(2), b=4.3118(4), c=11.017(1) Å, ,=91.683(2)° for RE=Eu. The refinement [I>2,,(I)] converged to the final residuals R1/wR2=0.0229/0.0589, 0.0411/0.1114, and 0.0342/0.0786 for Yb2Ga4Ge6, Yb3Ga4Ge6, and Eu3Ga4Ge6, respectively. The structures of these two families of compounds can be described by a Zintl concept of bonding, in which the three-dimensional [Ga4Ge6]n, framework serves as a host and electron sink for the electropositive RE atoms. The structural relation of RE3Ga4Ge6 to of Yb2Ga4Ge6 lies in a monoclinic distortion of the orthorhombic cell of Yb2Ga4Ge6 and reduction of the [Ga4Ge6] network by two electrons per formula unit. The results of theoretical calculations of the electronic structure, electrical transport data, and thermochemical and magnetic measurements are also reported. [source] | |||||||||||||||||||