The Experts below are selected from a list of 2697 Experts worldwide ranked by ideXlab platform

Gorky Shaw - One of the best experts on this subject based on the ideXlab platform.

  • Metastable inhomogeneous vortex configuration with non-uniform filling fraction inside a Blind Hole array patterned in a BSCCO single crystal and concentrating magnetic flux inside it
    Superconductor Science and Technology, 2016
    Co-Authors: Gorky Shaw, S. S. Banerjee, Tsuyoshi Tamegai, Hermann Suderow
    Abstract:

    Using magneto-optical imaging, we map the local magnetic field distribution inside a hexagonally ordered array of Blind Holes patterned in BSCCO single crystals. The nature of the spatial distribution of local magnetic field and shielding currents across the array reveals the presence of a non-uniform vortex configuration partially matched with the Blind Holes at sub-matching fields. We observe that the filling fraction is different in two different regions of the array. The mean vortex configuration within the array is described as a patchy vortex configuration with the patches having different mean filling fraction. The patchy nature of the vortex configuration is more pronounced at partial filling of the array at low fields while the configuration becomes more uniform with a unique filling fraction at higher fields. The metastable nature of this patchy vortex configuration is revealed by the application of magnetic field pulses of fixed height or individual pulses of varying height to the array. The metastability of the vortex configuration allows a relatively easy way of producing flux reorganization and flux focusing effects within the Blind Hole array. The effect of the magnetic field pulses modifies the vortex configuration within the array and produces a uniform enhancement in the shielding current around the patterned array edges. The enhanced shielding current concentrates magnetic flux within the array by driving vortices away from the edges and towards the center of the array. The enhanced shielding current also prevents the uninhibited entry of vortices into the array. We propose that the metastable patchy vortex configuration within the Blind Hole array is due to a non-uniform pinning landscape leading to non-uniform filling of individual Blind Holes.

  • Metastable magnetization response of the vortex state due to patterned Blind Hole pins
    Physica C: Superconductivity and its Applications, 2010
    Co-Authors: S. S. Banerjee, Gorky Shaw, Jaivardhan Sinha, Shyam Mohan, Pabitra Mandal
    Abstract:

    We show that nano-patterning a superconductor with a hexagonally ordered array of Blind Holes produces significant magnetic field sweep rate dependent metastable bulk magnetization response. Our results are explained on the basis of a collective action of Blind Hole pinning centers which creates a barrier against vortex redistribution inside the patterned area. Evidence of this barrier is found via magneto-optical imaging.

Hermann Suderow - One of the best experts on this subject based on the ideXlab platform.

  • Metastable inhomogeneous vortex configuration with non-uniform filling fraction inside a Blind Hole array patterned in a BSCCO single crystal and concentrating magnetic flux inside it
    Superconductor Science and Technology, 2016
    Co-Authors: Gorky Shaw, S. S. Banerjee, Tsuyoshi Tamegai, Hermann Suderow
    Abstract:

    Using magneto-optical imaging, we map the local magnetic field distribution inside a hexagonally ordered array of Blind Holes patterned in BSCCO single crystals. The nature of the spatial distribution of local magnetic field and shielding currents across the array reveals the presence of a non-uniform vortex configuration partially matched with the Blind Holes at sub-matching fields. We observe that the filling fraction is different in two different regions of the array. The mean vortex configuration within the array is described as a patchy vortex configuration with the patches having different mean filling fraction. The patchy nature of the vortex configuration is more pronounced at partial filling of the array at low fields while the configuration becomes more uniform with a unique filling fraction at higher fields. The metastable nature of this patchy vortex configuration is revealed by the application of magnetic field pulses of fixed height or individual pulses of varying height to the array. The metastability of the vortex configuration allows a relatively easy way of producing flux reorganization and flux focusing effects within the Blind Hole array. The effect of the magnetic field pulses modifies the vortex configuration within the array and produces a uniform enhancement in the shielding current around the patterned array edges. The enhanced shielding current concentrates magnetic flux within the array by driving vortices away from the edges and towards the center of the array. The enhanced shielding current also prevents the uninhibited entry of vortices into the array. We propose that the metastable patchy vortex configuration within the Blind Hole array is due to a non-uniform pinning landscape leading to non-uniform filling of individual Blind Holes.

J. Rechberger - One of the best experts on this subject based on the ideXlab platform.

  • Investigation of several PVD coatings for Blind Hole tapping in austenitic stainless steel
    Surface & Coatings Technology, 2005
    Co-Authors: A.e. Reiter, B. Brunner, M. Ante, J. Rechberger
    Abstract:

    Abstract During the last 10 years, the usage of stainless steel materials increased continuously in various industrial applications. However the machineability of these materials is difficult, especially austenitic stainless steels. Blind Hole tapping in such materials is problematic due to difficult chip formation, chip transport, the tendency of cold-welding and build-up edges on the tool. HSS-tools are commonly used for tapping. The surface is either untreated, annealed in steam or coated with PVD. In most cases TiN, TiCN or TiAlN coatings are used. In this study, Blind Hole tests were accomplished with HSS M8-taps in 1.4571 austenitic stainless steel. The tools were coated with hard coatings such as CrN, CrC, TiN, TiAlN, CrAlN; lubricant coatings such as WC/C and DLC, or double layers such as TiCN + WC/C. To investigate the behavior of the different coatings in this cutting process, the cutting torque maxima, the torque slope and different quality criteria for the finished thread were analyzed. The used tools were analyzed by SEM regarding tool wear and cold welding. In addition mechanical properties such as hardness, abrasive wear resistance and friction coefficient were measured. To conclude which coating is suited for this application the combined analysis of the machining data, the SEM-investigations and the mechanical properties were conducted. Coatings with low friction coefficient have the lowest fluctuation of the cutting torque and are the only one having the ability to reduce the reverse torque by a half. Overcoating e.g. TiCN with DLC and WC/C this property will be preserved. In this case the excellent abrasive and adhesive wear resistance of TiCN was combined with excellent friction behavior and abrasive wear resistance of DLC. Out of the accomplished tests no precise conclusion about the lifetime can be made, but to obtain a stable Blind Hole threading process in austenitic stainless steel a coating system which combines excellent adhesive and abrasive wear resistance as well as excellent friction properties is required.

Hongchang Ding - One of the best experts on this subject based on the ideXlab platform.

  • A non-contact measurement method on size shape and position of deep cavity Blind Hole
    2009 International Conference on Mechatronics and Automation, 2009
    Co-Authors: Hongji Xu, Hongping Wang, Hongchang Ding
    Abstract:

    The paper puts forward a new high-precise noncontact measuring method combining photoelectricity and machinery in limited deep cavity to detect form and position of Blind Hole. System is composed of high-precise drive mechanism, endoscopic optical path, precision raster part, imaging acquisition and processing part. Endoscopic optical system is moved linearly through drive mechanism in limited deep cavity, high-resolution CCD camera acquires image of Blind Hole, then system completes form and position measurement of Blind Hole through image processing. The example indicates precise reaches 0.01 mm.

S. S. Banerjee - One of the best experts on this subject based on the ideXlab platform.

  • Metastable inhomogeneous vortex configuration with non-uniform filling fraction inside a Blind Hole array patterned in a BSCCO single crystal and concentrating magnetic flux inside it
    Superconductor Science and Technology, 2016
    Co-Authors: Gorky Shaw, S. S. Banerjee, Tsuyoshi Tamegai, Hermann Suderow
    Abstract:

    Using magneto-optical imaging, we map the local magnetic field distribution inside a hexagonally ordered array of Blind Holes patterned in BSCCO single crystals. The nature of the spatial distribution of local magnetic field and shielding currents across the array reveals the presence of a non-uniform vortex configuration partially matched with the Blind Holes at sub-matching fields. We observe that the filling fraction is different in two different regions of the array. The mean vortex configuration within the array is described as a patchy vortex configuration with the patches having different mean filling fraction. The patchy nature of the vortex configuration is more pronounced at partial filling of the array at low fields while the configuration becomes more uniform with a unique filling fraction at higher fields. The metastable nature of this patchy vortex configuration is revealed by the application of magnetic field pulses of fixed height or individual pulses of varying height to the array. The metastability of the vortex configuration allows a relatively easy way of producing flux reorganization and flux focusing effects within the Blind Hole array. The effect of the magnetic field pulses modifies the vortex configuration within the array and produces a uniform enhancement in the shielding current around the patterned array edges. The enhanced shielding current concentrates magnetic flux within the array by driving vortices away from the edges and towards the center of the array. The enhanced shielding current also prevents the uninhibited entry of vortices into the array. We propose that the metastable patchy vortex configuration within the Blind Hole array is due to a non-uniform pinning landscape leading to non-uniform filling of individual Blind Holes.

  • Metastable magnetization response of the vortex state due to patterned Blind Hole pins
    Physica C: Superconductivity and its Applications, 2010
    Co-Authors: S. S. Banerjee, Gorky Shaw, Jaivardhan Sinha, Shyam Mohan, Pabitra Mandal
    Abstract:

    We show that nano-patterning a superconductor with a hexagonally ordered array of Blind Holes produces significant magnetic field sweep rate dependent metastable bulk magnetization response. Our results are explained on the basis of a collective action of Blind Hole pinning centers which creates a barrier against vortex redistribution inside the patterned area. Evidence of this barrier is found via magneto-optical imaging.