Thermal Cycles and Residual Stresses in FSW of Aluminum Alloys: Experimental Measurements and Numerical Models
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): Luciano Buglioni , Leonardo N. Tufaro , Hernán G. Svoboda In the present work longitudinal residual stresses obtained by different methods, numerical and experimental, in Friction Stir Welding (FSW) process for AA7075 were analyzed. The experimental method employed for residual stresses measurements was sectioning, whereas the numerical is a finite element (FEM) thermomechanical coupled model which does not consider the stir in the material. The effect of travel speed during FSW was also analyzed, measuring with strain gages positioned in...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Dynamic Analysis of an Oscillating Membrane by Digital Holographic Interferometry
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): Nicolás Budini , Cecilia Mulone , Fabio M. Vincitorio In this work we performed an analysis of the deformations suffered by a membrane by means of the non-invasive nor destructive digital holographic interferometry technique (DHI). This technique consists in recording holograms of an object and combining their numerical reconstructions to detect small deformations, displacements or oscillations of the entire object or parts of it. De- pending on the experimental setup and the wavelength used for illumination, it is possible to detect vari...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Synthesis of a Structured Material Based on Compact Spheres Coated with Zn or Mg Spinel
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): Sonia Bocanegra , Adriana Ballarini , Osvaldo Scelza , Sergio de Miguel In this work, a synthesis method of coating with thin layers of MgAl2O4 or ZnAl2O4 over α-Al2O3 spheres were developed. The method consisted in the deposition of a primer of bohemite on the spheres, followed by the impregnation with a solution of Mg or Zn nitrates, and further thermal treatments in order to obtain MAl2O4 (M: Mg or Zn). This method was modified to improve the thickness and purity of the layer material. With this method, layers of uniform and adequate ...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Structural and Magnetic Changes Induced by Electron and Ion Irradiation on HOPG
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): Milagros Ávila , Lisandro Venosta , Noelia Bajales , Paula Bercoff In recent decades, many studies reported magnetism in carbon-based materials. This phenomenon was attributed to structural defects within the sample. Many authors showed an increase of magnetization in HOPG (Highly Oriented Pyrolytic Graphite) induced by proton bombardment, meanwhile the effect of electronic irradiation on the magnetic behavior has been unattended till now. The aim of this work is to contribute to the understanding of defect-induced effects on the structu...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Processing and Characterization of Open–Cell Aluminum Foams Obtained through Infiltration Processes
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): S. Báez–Pimiento , M.E. Hernández–Rojas , M.E. Palomar–Pardavé This work reports the fabricating of open–cell Al foams which were manufactured through infiltration processes employing a device with controlled atmosphere for the fusion and infiltration processes of the metal, which is separate from the heating furnace. The device allows controlling its internal atmosphere with an inert gas to protect the metal of the fast oxidation, avoiding the employment of a controlled atmosphere furnace (a furnace of this kind incorporate the...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Water Vapor Oxidation of Ferritic 441 and Austenitic 316L Stainless Steels at 1100°C for Short Duration
This study focus on the characterization of the oxide scales formed after different exposure times in the range of 2.5-20min. Raman spectroscopy, XRD, SEM and XPS have been used. For all exposure times, 316L forms a breakaway type thick oxide scale (rupture of the pre-existing passivating film) with iron oxides on its outer part and a mix of spinels with Fe, Cr and Ni for its inner part. For lower water vapor partial pressure, iron oxides are constituted of wüstite. For higher water vapor partial pressure, iron oxides are constituted of a layer of hematite over a layer of magnetite slightly enriched in chromium. Due to st...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Materials Surface Science Applied to the Investigation of Cultural Heritage Artefacts
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): Marc Aucouturier , Evelyne Darque-Ceretti The skill of ancient artisans manufacturing artistic or everyday artworks surprises the modern material scientists. We show, through the study of archaeological pieces, how laboratory research instruments use enlightens the fabrication processes of unique items at antic periods. The specificity of surface science research favouring non-invasive means for investigations on museum objects is emphasised. The examples concern: - Nanostructured layers on ceramic surface to obtain the so-called lustre eff...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
On the Cold Drawing of Poly-Ether-Ether-Ketone (PEEK) Tubes
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): C.D. Arenas , Alcar R. de la C. , E.B. Hermida The mechanical behaviour commonly referred as cold drawing (CD) is a phenomenon that occurs once the yield point is reached, in a thermoplastic material subjected to a uniaxial tensile test at constant strain rate. In effect, after yielding the sample undergoes a neck in its cross-sectional area, which then propagates along the entire useful length of the sample while the applied force remains constant. This phenomenon occurs in amorphous or semi-crystalline materials in a wide range of temper...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Densification and Phase Formation Kinetics in Composite Materials of WC Embedded in an Fe-Matrix
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): Esteban A. Álvarez , Carlos J.R. González Oliver , José Luis García This paper presents results corresponding to the densification of WC-Fe composites. Commercial WC (4NPO H.C. Starck) was mixed with iron (Fe) added from a precursor obtained via sol-gel route. Results of the kinetics of phase formation in materials obtained via this sol-gel route, which involves several precursors of W, Fe and C, plus the addition of colloidal alumina (Al2O3) are also reported. Samples with different concentrations of Fe were studied using a vertical d...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Pd/Ti Electrocatalyst in Technological Significance Reactions
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): M. del C. Aguirre , A.S. Fuentes , A.F. Filippin New materials operating as future electrocatalysts into fuel cells or in environmental remediation processes are continuously under research. Here we studied palladium modified electrodes, such as Pd/Ti and Pd/GC (glassy carbon), which are electrochemically built and used in chromate detection, in oxygen reduction and alcohols oxidation reaction. The palladium material electrodeposited at constant potential was characterized by X-ray diffraction, and scanning electron microscopy. The respons...
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Forewords
Publication date: 2015 Source:Procedia Materials Science, Volume 9 Author(s): Roberto D. Arce , Nicolás Budini , Javier A. Schmidt (Source: Procedia Materials Science)
Source: Procedia Materials Science - July 3, 2015 Category: Materials Science Source Type: research
Influence of Electronic Irradiation on Failure and Hardness Properties of Pure Silica Glasses
Publication date: 2014 Source:Procedia Materials Science, Volume 7 Author(s): M. Barlet , J-M. Delaye , M. Gennisson , R. Caraballo , B. Boizot , D. Bonamy , C.L. Rountree This paper's focus is the failure and hardness properties of pure amorphous silica (Corning 7980®) after β-irradiation at different doses (0-2 GGy). Crack propagation takes place in the SCC regime (10-7-10-10 m.s-1) and Vickers indentation techniques probe the hardness properties of the samples. Irradiation is found to create point defects which mainly include E’ centers, Non-Bridging Oxygen Hole Centers and Peroxy Radicals. β-irradiation...
Source: Procedia Materials Science - December 19, 2014 Category: Materials Science Source Type: research
Gas Solubility and Diffusion in Oxide Glasses – Implications for Nuclear Wasteforms
Publication date: 2014 Source:Procedia Materials Science, Volume 7 Author(s): James F. Shackelford Gas solubility and diffusion in oxide glasses define the overall mechanisms of gas transport in these materials. There are numerous practical aspects of this transport with substantial commercial implications, e.g., gas separation, the outgassing and leak testing of vacuum systems, the thermal oxidation of silicon, and the focus of this conference: nuclear wasteforms. The fundamentals of gas transport are defined in regard to gas solubility and diffusion in rigid glasses below the glass transition temperature, including ...
Source: Procedia Materials Science - December 19, 2014 Category: Materials Science Source Type: research
Material Transformation: Interaction between Nuclear and Electronic Energy Losses
Publication date: 2014 Source:Procedia Materials Science, Volume 7 Author(s): M. Toulemonde , W. Assmann , Y. Zhang , M. Backman , W.J. Weber , C. Dufour , Z.G. Wang The interaction between nuclear and electronic energy losses induced by an individual ion are described and illustrated by four different experiments. Each experiment shows the different behaviors of the combined interactions. Defects created by nuclear energy loss are annealed by electronic energy loss in Fe by ions in the GeV energy regime, showing a competitive interaction (1+1<1). The sputtering of Ti is enhanced by electronic excitation ...
Source: Procedia Materials Science - December 19, 2014 Category: Materials Science Source Type: research
Discussion on the Structural Origins of the Fracture Toughness and Hardness Changes in Rapidly Quenched Borosilicate Glasses: A Molecular Dynamics Study
Publication date: 2014 Source:Procedia Materials Science, Volume 7 Author(s): L.-H. Kieu , D. Kilymis , J.-M. Delaye , S. Peuget Understanding radiation effects in nuclear glasses is important in order to assess their long term behaviour in a geological repository. In this paper, the results obtained by classical molecular dynamics about the mechanical properties of a simplified SiO2 – B2O3 – Na2O glass with the same molar proportions as in the real French nuclear glass were reviewed. A pristine and a disordered structure, representative of the irradiated one, were prepared in order to address the question of t...
Source: Procedia Materials Science - December 19, 2014 Category: Materials Science Source Type: research
