San Martín, Argentina
San Martín, Argentina

Time filter

Source Type

Tumminello S.,CONICET | Tumminello S.,Instituto Sabato | Del Negro N.,Instituto Sabato | Carrascal C.,CONICET | And 3 more authors.
Journal of Phase Equilibria and Diffusion | Year: 2017

Cu-In-Sn alloys are among the suggested materials to replace Pb-Sn alloys traditionally used in joining processes by the electronic industry. Thorough thermodynamic understanding is required for the selection/design of adequate and efficient alloys for specific applications. Understanding the effects that high cost elements such as In have on microstructure and phase stability is imperative for industrial use. In this work ternary alloys were prepared by melting high purity elements (5N) for selected compositions of the 17 at.% Cu isopleth, and cooling down to reproduce process conditions. Chemical composition was determined using scanning electron microscopy equipped with electron probe microanalysis. Measurements of transition temperatures were done by heat-flux differential scanning calorimetry. We present a comprehensive comparison between our experimental results and phase diagram calculations using Liu et al. (J Electron Mater 30:1093, 2001) thermodynamic description based in the CALPHAD method, available in the literature. © 2017 ASM International


Zadorozne N.S.,National University of Misiones | Giordano C.M.,Gerencia Materiales | Giordano C.M.,Instituto Sabato | Rebak R.B.,General Electric | And 3 more authors.
Corrosion | Year: 2015

It is reported in the literature that alloy C-22 (N06022) was found to be susceptible to stress corrosion cracking (SCC) in presence of bicarbonate ions, at temperatures higher than 60°C and anodic applied potentials in the order of 400 mVSCE, (where SCE is the saturated calomel electrode) when using slow strain rate tests (SSRTs). This potential range of cracking susceptibility was associated with the instability of a film that may form on the surface. In order to elucidate the role of the alloying elements on the SCC susceptibility of nickel (Ni)-based alloys, four alloys - C-22 (N06022), 600 (N06600), 800H (N08800) and Ni-201 (N02201) - were tested under the same conditions. Results showed that even though C-22, 600, and 800 may have similar electrochemical anodic behavior, only C-22 may present a clear case of SCC at anodic potentials. © 2015, NACE International.


Pasianot R.C.,Gerencia Materiales | Perez R.A.,CONICET | Perez R.A.,Instituto Sabato
Journal of Nuclear Materials | Year: 2013

We revisit the ultra-fast diffusion characteristics of Fe, Co, Ni, and Cu solutes, in the hcp hosts Ti and Zr, by using Density Functional Theory. The energetics of several point defect configurations, deemed relevant for solute diffusion, is evaluated. The results support the long standing beliefs that the diffusing species is interstitial in nature, and that some kind of complexing is involved at low temperatures. Though quantitative agreement with experiment is difficult to assess, we show that a rather simple dissociative model is able to rationalize the observed trends, in particular, why the Arrhenius graphs are straight for Ti whereas, generally, they are curved downwards for Zr. © 2012 Elsevier B.V. All rights reserved.


Pasianot R.C.,Gerencia Materiales | Pasianot R.C.,CONICET | Pasianot R.C.,Instituto Sabato
Journal of Nuclear Materials | Year: 2016

We study the structure of several standard and non-standard self-interstitial configurations in a series of hcp metals, by using Density Functional Theory as embodied in the computer codes SIESTA and WIEN2k. The considered metals include Be, Mg, Ti, Zr, Co, Zn, and Cd, thus spanning the whole range of experimental c/a ratios, different kinds of bonding, and even magnetism (Co). The results show the importance of low symmetry configurations, closely related to the non-basal crowdion, in order to rationalize the experimental data on self-interstitial structure and migration. © 2016 Elsevier B.V.


Corvalan C.H.,Gerencia Materiales | Vega D.R.,Gerencia Investigacion y Aplicaciones
Acta Crystallographica Section E: Structure Reports Online | Year: 2013

The title compound {systematic name: [2-(1-hydroxycyclohexyl)-2-(4- methoxyphenyl)ethyl]dimethylazanium benzenesulfonate monohydrate}, C 17H28NO2 +·C6H 5O3S-·H2O, is a besylate salt hydrate of the antidepressant drug venlafaxine. In the crystal, besylate anions and water molecules self-assemble, forming hydrogen-bonded dimers linked around inversion centers, with graph set R 44(6). The crystal packing features a chain of alternate dimers and venlafaxine cations in the b-axis direction with the components linked by O-H⋯O hydrogen bonds and C-H⋯O and C-H⋯π interactions. This is the first example of a venlafaxine cation with a closed conformation, as it features an intramolecular N-H⋯O interaction involving the protonated N atom.

Loading Gerencia Materiales collaborators
Loading Gerencia Materiales collaborators