INTERNALLY OXIDIZED, DISPERSION STRENGTHENED AG FOR HIGH-TEMPERATURE SUPERCONDUCTOR WIRES

HIGH-TEMPERATURE SUPERCONDUCTOR (HTS) COMPOSITE WIRES ARE BEING STRENGTHENED USING INTERNALLY OXIDIZED, DISPERSION STRENGTHENED (ODS) SILVER. CURRENT METHODS OF MANUFACTURE OF STATE-OF-THE-ART HTS COMPOSITE WIRES THAT CONSIST OF CERAMIC SUPERCONDUCTOR FILAMENTS ENCASED IN A SILVER (AG) SHEATH, WEAKEN THE AG SHEATH, RESULTING IN REDUCED HTS COMPOSITE STRENGTHS. THE LOW STRENGTH OF THE COMPOSITE WIRES IS A MAJOR OBSTACLE IN THE DEVELOPMENT OF HTS WIRES FOR APPLICATIONS REQUIRING ROBUST CONDUCTORS SUCH AS POWER TRANSMISSION CABLES, SMES, AND MOTORS. THE ONE METHOD OF INCREASING THE STRENGTH OF THE SHEATH, WHILE MAINTAINING THE CHEMICAL COMPATIBILITY AND OXYGEN PERMEABILITY OF AG IS ODS. BECAUSE THE REQUIRED STRENGTHS CANNOT BE OBTAINED USING COMMERCIALLY AVAILABLE ODS-AG MATERIALS AND PROCESSES, THE RESEARCH IS BEING DIRECTED TOWARD EVALUATING ODS-AG MATERIALS USING NOVEL PROCESSING TECHNIQUES IN THE CONTEXT OF HTS COMPOSITE PROCESSING. PROCESS-PROPERTY-MICROSTRUCTURE RELATIONSHIPS FOR THE ODS-AG MATERIALS ARE BEING OBTAINED. BY USING STATISTICALLY DESIGNED EXPERIMENTAL TECHNIQUES, A QUANTITATIVE EXPRESSION OF THE MECHANICAL PROPERTIES OF THE NOVEL ODS-AG MATERIAL AS A FUNCTION OF THE PROCESS PARAMETERS (TEMPERATURE, OXYGEN ACTIVITY, TIME, AND STRAIN) RELEVANT TO HTS COMPOSITE WIRE FABRICATION RESULTS. THIS EVALUATION SCHEME ENABLES THE IDENTIFICATION OF THE OPTIMUM ODS-AG MATERIAL (COMPOSITION AND PROCESS) FOR INTEGRATION WITH HTS IN COMPOSITE FORM.