The formation and enhancement of texture in a Bi-system superconductor

The powder-in-tube method was used to produce Ag-sheathed samples using two precursor methods to study the texture formation of the superconducting phases in Bi-system tapes. Experimental results showed that the texture of the 2223 phase results from that of the 2212 grains and the formation of the 2212 phase texture mainly originates with the oriented growth of grains due to residual stress produced during processing. Based on experimental results, a new, prepressing process was proposed to enhance the texture of the superconducting phases, and, therefore, improve the critical current densities of the composite tapes.