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Surface properties and wetting behavior of liquid Ag-Sb-Sn alloys
Sklyarchuk V.,Plevachuka Yu.,Kaban I.,Novakovic R.
Journal of Mining and Metallurgy, Section B : Metallurgy , 2012, DOI: 10.2298/jmmb120719055s
Abstract: Surface tension and density measurements of liquid Ag-Sb-Sn alloys were carried out over a wide temperature range by using the sessile drop method. The surface tension experimental data were analyzed by the Butler thermodynamic model in the regular solution approximation. The wetting characteristics of these alloys on Cu and Ni substrates have been also determined. The new experimental results were compared with the calculated values as well as with data available in the literature.
Calculation of the thermodynamic properties of liquid Ag–In–Sb alloys
Journal of the Serbian Chemical Society , 2006,
Abstract: The results of calculations of the thermodynamic properties of liquid Ag–In–Sb alloys are presented in this paper. The Redlich–Kister–Muggianu model was used for the calculations. Based on known thermodynamic data for constitutive binary systems and available experimental data for the investigated ternary system, the ternary interaction parameter for the liquid phase in the temperature range 1000–1200 K was determined. Comparison between experimental and calculated results showed their good mutual agreement.
Determination of the thermodynamic properties of liquid Ag-Sb-Sn system by equilibrium saturation method  [PDF]
J. Romanowska,L. Bencze
Journal of Achievements in Materials and Manufacturing Engineering , 2011,
Abstract: Purpose: The interaction of lead-free solders with a copper substrate is an essential issue for the reliability of solder joints. In order to understand this interaction, the knowledge of thermodynamic and other physical properties of several ternary systems such as Ag-Sb-Sn system is necessary. The aim of this work was to determine the activities of all components in Ag-Sb-Sn alloy.Design/methodology/approach: The investigation of this system was carried out using the equilibrium saturation (ES) method. The ES measurements were performed at 1273, 1373 and 1473 K. As the latter method is a comparative one, a Sn-Sb alloy was accepted as a reference alloy, where a formula for the Sb activity proposed by J nsson and verified by Vassiliev was accepted.Findings: In the frame of the presented experiments the activity of Sb was determined by ES method.Research limitations/implications: The activity of Sb was obtained by ES and fitted to the Redlich-Kister-Muggianu (RKM) model.Practical implications: A knowledge of multi-component phase equilibrium can provide the alloy developer with specific data enabling finding alloys that meet certain criteria. Phase diagrams are built on the basis of experimental data and the reliability of phase diagrams depends on the reliability of the experimental data used for the optimisation. Hence it is advantageous to use various source of data obtained by several methods and when the data of different source agree (like the ones presented in this paper) it proves their reliability. Data presented in this paper will be used for Ag-Sb-Sn phase diagram optimisation in the frame of the COST Action MP0602.Originality/value: Sb activity values in Ag-Sb-Sn alloys obtained by ES and activity values of Sb, Ag and Sn calculated using the RKM model.
Abnormal growth of Ag3Sn intermetallic compounds in Sn-Ag lead-free solder
Jun Shen,Yongchang Liu,Houxiu Gao
Chinese Science Bulletin , 2006, DOI: 10.1007/s11434-006-2043-y
Abstract: The abnormal growth of Ag3Sn intermetallic compounds in eutectic Sn-3.5% Ag solder was investigated through high-temperature aging treatment. Microstructural evolutions of this solder before and after the aging treatment were observed by optical microscopy and scanning electron microscopy. Precise differential thermal analysis was made to study the changes in enthalpies of the solder under different conditions. The results reveal that the water-cooled solder is in metastable thermodynamic state due to the high free energy of Ag3Sn nanoparticles, which sporadically distribute in the matrix as second-phase. The second-phase Ag3Sn nanoparticles aggregate rapidly and grow to form bulk intermetallic compounds due to the migration of grain boundary between primary Sn-rich phase and the Ag3Sn nanoparticles during high temperature aging treatment.
Phase equilibria investigation and alloys characterization in Sn-In-Ag system  [PDF]
Milosavljevi? Aleksandra R.,?ivkovi? Dragana T.,Manasijevi? Dragan,Talijan Nade?da
Hemijska Industrija , 2008, DOI: 10.2298/hemind0803148m
Abstract: Lead-free soldering has become very popular in the world recently, especially in electronics, because of high ecological demands in industry. Some of lead-free solder alloys are already used in electronic industry, but despite that investigations are still going in order to find suitable replacement for Pb-Sn standard solder. In this paper phase equilibria and characterization of Sn-In-Ag alloys in section In:Ag = 7:3 are investigated. The results of phase diagram calculation are obtained by ThermoCalc software, and characteristic temperatures by DSC method. The results of XRD analysis, optical microscopy, microhardness and electrical conductivity are also presented. These results are given in order to contribute the knowledge about lead-free solders, especially Sn-In-Ag solder alloys, which are potential candidates for replacement standard lead solders.
Investigation of mechanicaland structural characteristics of some alloys in Ag-rich corner of Ag-Cu-Sn system
Marjanovi? S.,Guskovi? D.,Truci? M.,Marjanovi? B.
Journal of Mining and Metallurgy, Section B : Metallurgy , 2007, DOI: 10.2298/jmmb0702177m
Abstract: Results of investigation of mechanical and structural characteristics of some Ag-rich alloys in Ag- Cu-Sn system are presented in this paper. Starting samples were four small billets with different contents of constituting elements - Ag90Cu5Sn5, Ag85Cu5Sn10, Ag85Cu10Sn5, Ag80Cu10Sn10 (at%), prepared from p.a. metals Sn, Ag, Cu by melting in electro-inductive furnace under air atmosphere and additional reductant and cast into bars of square shape, dimensions 1x1x10cm. Mechanical characteristics, such as hardness and microhardness, electroconductivity and microstructure, were observed before and after a series of passes through a grooved roll stand (cold rolling).
Spin-Diffusion Lengths in Dilute Cu(Ge) and Ag(Sn) Alloys  [PDF]
Q. Fowler,B. Richard,A. Sharma,N. Theodoropoulou,R. Loloee,W. P. Pratt Jr.,J. Bass
Physics , 2008, DOI: 10.1016/j.jmmm.2008.08.043
Abstract: We use current-perpendicular-to-plane (CPP) exchange-biased spin-valves to directly measure spin diffusion lengths lsf for N = Cu(2.1 at.%Ge) and Ag(3.6 at.%Sn) alloys. We find lsf(Cu2%Ge)) = 117+10-6 nm and lsf(Ag4%Sn)= 39 +/- 3 nm. The good agreement of this lsf(Cu2%Ge) with the value lsf(Cu2%Ge) = 121 +/- 10 nm derived from an independent spin-orbit cross-section measurement for Ge in Cu, quantitatively validates the use of Valet-Fert theory for CPP-MR data analysis to layer thicknesses several times larger than had been done before. From the value of lsf(Ag4%Sn), we predict the ESR spin-orbit cross-section for Sn impurities in Ag.
Microstructural characteristics and electrical resistivity of rapidly solidified Co-Sn alloys
Jinfeng Xu,Nan Wang,Bingbo Wei
Chinese Science Bulletin , 2004, DOI: 10.1360/04ww0066
Abstract: The rapid solidification behavior of Co-Sn alloys was investigated by melt spinning method. The growth morphology of αCo phase in Co-20%Sn hypoeutectic alloy changes sensitively with cooling rate. A layer of columnar αCo dendrite forms near the roller side at low cooling rates. This region becomes small and disappears as the cooling rate increases and a kind of very fine homogeneous microstructure characterized by the distribution of equiaxed αCo dendrites in γCo3Sn matrix is subsequently produced. For Co-34.2%Sn eutectic alloy, anomalous eutectic forms within the whole range of cooling rates. The increase of cooling rate has two obvious effects on both alloys: one is the microstructure refinement, and the other is that it produces more crystal defects to intensify the scattering of free electrons, leading to a remarkable increase of electrical resistivity. Under the condition that the grain boundary reflection coefficient r approaches 1, the resistivity of rapidly solidified Co-Sn alloys can be predicted theoretically.
Thermodynamic modelling of precious metals alloys
Bernd Kempf,Siegfried Schmauder
Gold Bulletin , 1998, DOI: 10.1007/BF03214761
Abstract: The alloy system Au Ag Pd Pt Sn is described with the help of the thermodynamic software ‘Chemsage’ and a specially modelled dataset. Calculations on the stability of precipitated phases show good agreement with experimental results from hardness tests and metallography and thereby provide a better understanding of the observed material properties. The use of such modelling provides an efficient tool for faster and more direct development of precious metal alloys.
Microstructural and thermal analysis of Cu-Ni-Sn-Zn alloys by means of SEM and DSC techniques  [PDF]
G. Wnuk,M. Zielińska
Archives of Materials Science and Engineering , 2009,
Abstract: Purpose: The urgent need to find new, non toxic, high temperature solders caused the abundance of research on multicomponent systems, so as to find new materials that could substitute lead-containing solders.Design/methodology/approach: In the paper Cu-Ni-Sn-Zn alloys were studied by differential scanning calorymetry (DSC) in argon atmosphere using a heating rate of 10 Kmin-1 and a cooling rate of 15 Kmin-1. There were determined heat effects and start and finish temperature of phase transitions. Each sample was heated and cooled twice. At the second run, Zn concentration was smaller (as Zn is a volatile component).Findings: Zn influence on phase transformations was established. For the second run, when Zn activity is smaller, heats and temperature of transformations are higher.Research limitations/implications: These experimental results, combined with other thermodynamic properties of the studied alloy, enable phase diagram calculation in the frame of the COST action MP0602.Practical implications: Phase diagrams of the studied alloys allow finding appropriate solder materials.Originality/value: The paper presents an influence of zinc on temperature and heats of transformations in Cu-Ni-Sn-Zn alloys and the microstructure of these alloys.
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