The Experts below are selected from a list of 5169 Experts worldwide ranked by ideXlab platform

Ma Qia - One of the best experts on this subject based on the ideXlab platform.

  • metal injection moulding of non spherical titanium powders processing microstructure and mechanical properties
    Journal of Manufacturing Processes, 2018
    Co-Authors: Ali Dehghanmanshadi, Ma Qia, Yunhui Che, D H Stjoh, Matthew S. Dargusch
    Abstract:

    © 2017 The Society of Manufacturing Engineers The critical processing parameters for metal injection moulding (MIM) of titanium using inexpensive non-spherical hydride-dehydride (HDH) powders with an average particle size of 45 μm were established through a series of laboratory scale injection moulding investigations. A Slow Heating Rate of 1.0 K/min during thermal de-binding and sintering resulted in samples with negligible or limited distortion and nearly uniform shrinkage in all directions. Sintering at 1250 °C for 120 min was identified to be a suitable condition for MIM of HDH Ti, which produced samples with a relative density of 96.5%, uniform shrinkage of 13.9% along the length direction and 14.7% along the thickness direction. The as-sintered samples achieved a tensile strength of 395 MPa and elongation of 12.5%. The promising tensile elongation indicates that MIM of HDH titanium powder can cope with the relatively high oxygen level in the initial inexpensive HDH Ti powder as well as the unavoidable further increase in oxygen level during the MIM cycle.

Yuri Grin - One of the best experts on this subject based on the ideXlab platform.

  • preparation of titanium diboride tib2 by spark plasma sintering at Slow Heating Rate
    Science and Technology of Advanced Materials, 2007
    Co-Authors: Jurgen Schmidt, Marian Boehling, Ulrich Burkhardt, Yuri Grin
    Abstract:

    A systematic study of the spark plasma sintering of TiB2 starting from mixture of elemental powders was performed to investigate the temperature distribution between pressing tool and sinter body. The reaction mechanism and time-dependant evolution of the sintering behavior are established. The simultaneous application of pulsed high dc current and load leads to a microstructure with needle-shaped grains. Electron backscattering diffraction analyses show the preferred orientation of small crystallites parallel to the pressing direction.

Jürgen Gmehling - One of the best experts on this subject based on the ideXlab platform.

  • High pressure solid–solid and solid–liquid transition data for long chain alkanes
    The Journal of Chemical Thermodynamics, 2008
    Co-Authors: J.j.b. Machado, Theo W. De Loos, E. Christian Ihmels, Kai Fischer, Jürgen Gmehling
    Abstract:

    Abstract The thermal behavior, upon Heating, was studied for four alkanes: eicosane, tetracosane, triacontane, and tetracontane at pressures from (10 to 150) MPa. Using a transitiometer, the calorimetric signal, pressure, and temperature were measured at a very Slow Heating Rate to guarantee thermal equilibrium. It was found that from the compounds studied, eicosane was the only one that did not present a solid–solid transition; the other compounds show a solid–solid transition a few Kelvin below the solid–liquid transition temperature. This solid–solid transition disappears when the pressure is increased in a triple point of type: solid + solid + liquid.

Jurgen Schmidt - One of the best experts on this subject based on the ideXlab platform.

  • preparation of titanium diboride tib2 by spark plasma sintering at Slow Heating Rate
    Science and Technology of Advanced Materials, 2007
    Co-Authors: Jurgen Schmidt, Marian Boehling, Ulrich Burkhardt, Yuri Grin
    Abstract:

    A systematic study of the spark plasma sintering of TiB2 starting from mixture of elemental powders was performed to investigate the temperature distribution between pressing tool and sinter body. The reaction mechanism and time-dependant evolution of the sintering behavior are established. The simultaneous application of pulsed high dc current and load leads to a microstructure with needle-shaped grains. Electron backscattering diffraction analyses show the preferred orientation of small crystallites parallel to the pressing direction.

Yukihiko Okumura - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Heating Rate and coal type on the yield of functional tar components
    Proceedings of the Combustion Institute, 2017
    Co-Authors: Yukihiko Okumura
    Abstract:

    Abstract Pyrolysis with a rapid Heating Rate can be expected to achieve a higher yield of volatile matter than that with a Slow Heating Rate. Therefore, this technique is attracting attention as a means to obtain useful liquid or gaseous materials in high yields. However, a detailed study on the tar components and increasing/decreasing yields of chemical materials involved in various-Heating-Rate pyrolysis has not been reported. Hence, in order to contribute to the advanced chemical applications of pyrolysis products, this study quantitatively investigated the effects of Heating Rate and coal type on the yield of functional coal-tar components using GC–MS. The main outcomes of the study are as follows: (1) The yields of cyclized aromatic hydrocarbons such as benzene, styrene, indene, naphthalene, and PAH (3- to 5-membered rings) increased with increasing Heating Rate. (2) A systematic method for obtaining the yields of functional coal-tar components was developed. The tar yield increased linearly with the H/C atomic ratio in various coal types. (3) The yield of indene, which can be used as a functional raw material, increased proportionally with increasing H/C ratio. The yield of fluorene, which can be used to enhance resin functionality, increased only for coals with a high H/C ratio.