Characterization of nano-composite M-2411/Y-123 thin films by electron backscatter diffraction and in-field critical current measurements

Thin films of nano-composite Y-Ba-Cu-O (YBCO) superconductors containing nano-sized, non-superconducting particles of Y2Ba 4CuMOx (M-2411 with M = Ag and Nb) have been prepared by the PLD technique. Electron backscatter diffraction (EBSD) has been used to analyze the crystallographic orientation of nano-particles embedded in the film microstructure. The superconducting YBa2Cu3O7 (Y-123) phase matrix is textured with a dominant (001) orientation for all samples, whereas the M-2411 phase exhibits a random orientation. Angular critical current measurements at various temperature (T) and applied magnetic field (B) have been performed on thin films containing different concentration of the M-2411 second phase. An increase in critical current density J c at T < 77 K and B < 6 T is observed for samples with low concentration of the second phase (2 mol % M-2411). Films containing 5 mol % Ag-2411 exhibit lower Jc than pure Y-123 thin films at all fields and temperatures. Samples with 5 mol % Nb-2411 show higher Jc(B) than phase pure Y-123 thin films for T < 77 K. © 2010 IOP Publishing Ltd.

Performance comparison of Stellite 6® deposited on steel using supersonic laser deposition and laser cladding

Stellite 6® powders were deposited on carbon steel using Supersonic Laser Deposition. The microstructure and performance of the coatings were examined using SEM, optical microscopy, EDS, XRD, microhardness testing and pin-on-disc wear testing. The results showed that the microstructure and wear behaviour of the most successful SLD deposition conditions with N2 at a pressure of 30bar, a temperature of 450°C and a deposition power of 1.5kW were compared with that of optimised laser cladding. © 2012 Elsevier B.V.