SURFACE MODIFICATION ON OXIDE SUPERCONDUCTOR USING C02 LASER

Powder-sintered oxide superconductor does not allow the flow of superconducting current uniformly and the flow is concentrated on the surface. Further, it is poor in mechanical strength. Thus, properties of oxide superconductor ere so sensitive to their surface condition that some substantial modifications of the material are necessary. Powder sintered superconductor surfaces have been modified using C0₂ laser irradiation, The mechanical strength almost doubled and the current density was about 25 times greater after irradiation. The modified layer showed not only the elimination of many pores among grain boundaries but also preferred orientation of crystal grains.