Journal: Journal of Materials Science

Abbreviation

J. Mater. Sci.

Publisher

Springer

Journal Volumes

ISSN

0022-2461
1573-4803

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Publications 1 - 10 of 43
  • A quenching apparatus for the gaseous products of the solar thermal dissociation of ZnO
    Item type: Conference Paper
    Gstoehl, D.; Brambilla, A.; Schunk, L. O.; et al. (2008)
    Journal of Materials Science
  • Explaining the heat capacity of wood constituents by molecular vibrations
    Item type: Journal Article
    Thybring, Emil E. (2014)
    Journal of Materials Science
    The heat capacity of wood and its constituents is important for the correct evaluation of many of their thermodynamic properties, including heat exchange involved in sorption of water. In this study, the dry state heat capacity of cellulose, hemicelluloses and lignin are mathematically described by fundamental physical theories relating heat capacity with molecular vibrations. Based on knowledge about chemical structure and molecular vibrations derived from infrared and Raman spectroscopy, heat capacities are calculated and compared with experimental data from literature for a range of bio- and wood polymers in the temperature range 5–370 K. A very close correspondence between experimental and calculated results is observed, illustrating the possibility of linking macroscopic thermodynamic properties with their physical nano-scale origin.
  • The influence of constrictivity on the effective transport properties of porous layers in electrolysis and fuel cells
    Item type: Journal Article
    Holzer, L.; Wiedenmann, D.; Münch, B.; et al. (2013)
    Journal of Materials Science
  • Influence of the brazing parameters on microstructure, residual stresses and shear strength of diamond-metal joints
    Item type: Conference Paper
    Buhl, Sebastian; Leinenbach, Christian; Spolenak, Ralph; et al. (2010)
    Journal of Materials Science
  • The effect of strain rate on the mechanisms of plastic flow and failure of an ECAE AZ31B magnesium alloy
    Item type: Journal Article
    Kannan, Vignesh; Ma, Xiaolong; Krywopusk, Nicholas M.; et al. (2019)
    Journal of Materials Science
    Plastic flow is studied as a function of strain rate for uniaxial compression along the principal directions of an AZ31B magnesium alloy processed by equal channel angular extrusion across 8 decades of strain rate. The effect of strain rate on flow stress is found to be a function of loading orientation. Work hardening rates are also found to vary with strain rate and orientation. In situ high-speed imaging reveals the prominence of heterogeneous deformation at small macroscopic strains. Postmortem electron microscopy further shows significant texture reorientation under multiple orientations of loading—some aided by twins and others by dislocation slip. It is observed that twin activity is more favorable at high strain rates. While very little twinning and significant grain growth were observed from complementary quasi-static experiments by Krywopusk et al. (unpublished), we observe significant twinning with negligible grain growth at high strain rates.
  • Elevated and cryogenic temperature micropillar compression of magnesium–niobium multilayer films
    Item type: Journal Article
    Thomas, Keith; Mohanty, Gaurav; Wehrs, Juri; et al. (2019)
    Journal of Materials Science
  • Viscosity and electrical conductivity of liquid Sn-Ti and Sn-Zr alloys
    Item type: Journal Article
    Plevachuk, Yu.; Mudry, S.; Sklyarchuk, V.; et al. (2007)
    Journal of Materials Science
  • Calcia-doped yttria-stabilized zirconia for thermal barrier coatings
    Item type: Journal Article
    Bhattacharya, Anup K.; Reinhard, Patrick; Steurer, Walter; et al. (2011)
    Journal of Materials Science
  • Contact damage of hard and brittle thin films on ductile metallic substrates: An analysis of diamond-like carbon on titanium substrates
    Item type: Journal Article
    Bernoulli, Daniel; Wyss, Andi; Raghavan, R.; et al. (2015)
    Journal of Materials Science
    Friction and wear minimizing coatings are crucial for applications in combustion engines and medical implants. Their performance is typically limited by mechanical failure especially due to local overload. In this work, the contact damage creation, evolution, and final morphology of hydrogenated diamond-like carbon (DLC)-coated titanium (Ti) substrates are investigated. The influence of the DLC film thickness and the elastic–plastic deformation of the Ti on the contact damage are studied by microindentation and static finite-element analysis. Film thickness, indenter radius, and applied load as well as the elastic–plastic deformation of the Ti are shown to significantly affect contact damage. A failure plot is presented with the location of first failure in the DLC and compared to the experimental observation. In addition, a case study with variable fracture toughness of the DLC and its influence on the failure plot is shown. The stress distribution in the DLC follows a transition from a membrane-like to a plate-like deformation behavior upon increasing the DLC film thickness. Thin DLC films reveal increased cracking in the inner zone of the indent, while thicker DLC films reveal pronounced edge cracking. These edge cracks were correlated to pop-ins in force–displacement curves upon microindentation. Finally, a film thickness optimization process is presented for hard and brittle films on soft and ductile metallic substrates.
  • Photonic response and temperature evolution of SiO2/TiO2 multilayers
    Item type: Journal Article
    Christidis, George; Fabrichnaya, Olga B.; Koepfli, Stefan M.; et al. (2021)
    Journal of Materials Science
    The microstructural and optical reflectivity response of photonic SiO2/TiO2 nanomultilayers have been investigated as a function of temperature and up to the material system’s melting point. The nanomultilayers exhibit high, broadband reflectivities up to 1350 °C with values that exceed 75% for a 1 μm broad wavelength range (600–1600 nm). The optimized nanometer sized, dielectric multilayers undergo phase transformations from anatase TiO2 and amorphous SiO2 to the thermodynamically stable phases, rutile and cristobalite, respectively, that alter their structural morphology from the initial multilayers to that of a scatterer. Nonetheless, they retain their photonic characteristics, when characterized on top of selected substrate foils. The thermal behavior of the nanometer sized multilayers has been investigated by differential thermal analysis (DTA) and compared to that of commercially available, mm-sized, annealed powders. The same melting reactions were observed, but the temperatures were lower for the nm-sized samples. The samples were characterized using X-ray powder diffraction before DTA and after annealing at temperatures of 1350 and 1700 °C. The microstructural evolution and phase compositions were investigated by scanning electron microscopy and energy-dispersive X-ray spectroscopy measurements. The limited mutual solubility of one material to another, in combination with the preservation of their optical reflectivity response even after annealing, makes them an interesting material system for high-temperature, photonic coatings, such as photovoltaics, aerospace re-entry and gas turbines, where ultra-high temperatures and intense thermal radiation are present.
Publications 1 - 10 of 43