Search for dissertations about: "niobium"

Showing result 1 - 5 of 52 swedish dissertations containing the word niobium.

  2. 1. Antenna Integrated Superconducting Mixers

    Author : Hans Ekström; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; tapered slotline antenna; mixer; double dipole antenna; superconducting; hot electron; receiver; Niobium; bolometer; trilayer junction; edge junction; Niobium Nitride; SIS;

    Abstract : This thesis investigates the prospects of some different superconducting mixers integrated with planar antennas for the millimeter and submillimeter regime. Two kinds of Superconductor/Insulator/Superconductor (SIS) tunnel junctions for use in mixers have been fabricated; Nb/PbBi edge junctions and Nb trilayer junctions. READ MORE

  4. 2. Charging Effects in Niobium Nanostructures

    Author : Torsten Henning; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : Three types of metallic nanostructures comprising niobium were investigated experimentally; in all three types, electric transport at very low temperatures was governed by Coulomb blockade effects. 1. READ MORE

  5. 3. Machinability of Single-phase Materials : Surface integrity and tool wear analysis

    Author : Mike Olsson; Industriell Produktion; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Machinability; Niobium; Tungsten; Oxygen-free copper; Surface integrity; Tool wear;

    Abstract : The quality and performance of products are particularly important in sectors such as research facilities and in the nuclear, military and space industries. These sectors make use of high-performance materials that are uncommon in other contexts and therefore place high requirements on personnel, machines and tools. READ MORE

  6. 4. Weldability of Cast Superalloys - Effect of homogenization heat treatments on hot cracking susceptibility of cast Alloy 718, ATI® 718Plus®, and Haynes® 282®

    Author : Sukhdeep Singh; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hot ductility; Segregation; Homogenization; Boron; Gleeble; Welding; Nickel-based superalloys; Varestraint; Hot cracking; Hot isostatic pressing; Niobium;

    Abstract : Precipitation hardened Ni- and Ni–Fe-based superalloys are used in high-temperature sections of aero engines owing to their superior mechanical properties compared to those of the other alloys. However, their better mechanical performance is accompanied by its own challenges during the manufacturing process. READ MORE

  7. 5. Hydrogen-induced distortions i bcc transition metals

    Author : Björn von Sydow; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; niobium; hydrogen diffusion; metal-hydrogen system; interatomic interaction potentitals; transition metals; distortions;

    Abstract : .... READ MORE