NIOBIUM TITANIUM MULTIFILAMENTARY MATERIALS WITH SILICON IN THE MATRIX

THE AIM OF THIS WORK IS TO EXPLORE FURTHER THE PROPERTIES OF NIOBIUM TITANIUM (NBTI) STRANDS WITH MATRICES CONTAINING SILICON (SI) FOR HIGH ENERGY PHYSICS APPLICATIONS. THERE ARE INDICATIONS THAT THE ADDITION OF SI TO THE MATRIX WILL HELP ELIMINATE THE NB BARRIER, IMPROVE THE CRITICAL CURRENT (JC), LOWER THE LOSSES, AND SIMPLIFY THE PROCESS, THUS LOWERING THE COSTS. THIS IMPROVEMENT IS APPLICABLE TO COARSE AND FINE FILAMENT MATERIALS. BECAUSE OF THE VERY PROMISING RESULTS AND THEIR POTENTIALLY BROAD APPLICATIONS, THE WORK WILL BE CONTUBYED, THE PREVIOUS WORK WITH CU-2.5 WT. % SI AND CU-3.5 WT. % SI MATRICES CONFIRMED EARLIER JAPANESE WORK AND SHOWED JC'S IN FINE WIRE MATERIAL WHICH WERE 13% HIGHER THAN THOSE FROM MATERIAL WITH AN 8% BARRIER. IT DID, HOWEVER, LEAVE MANY UNANSWERED QUESTIONS WHICH WILL BE ADDRESSED IN THIS PROJECT. PHASE I WILL (1) OBTAIN A BETTER UNDERSTANDING OF THE CHEMICAL AND MECHANICAL NATURE OF THE MATERIAL THAT IS FORMED AT THE INTERFACE BETWEEN THE SI CONTAINING MATRIX AND THE NBTI FILAMENTS, (2) DETERMINE MORE ABOUT THE DEPENDENCE OF THE MATERIAL'S PROPERTIES ON THE THERMOMECHANICAL CONDITIONS INVOLVED IN ITS FORMATION AND HOW THESE PROPERTIES AFFECT THE DRAWABILITY OF THE COMPOS.ITE ITSELF, (3) DETERMINE INFORMATION ON THE EXTENT TO WHICH ANNEALLING WILL BE REQUIRED IN THE FABRICATION OF THE COMPOSITES CONTAINING CU-2.5 WT. % SI AND CU-305 WT. % SI MATRICES, (4) ASCERTAIN IF FILAMENT UNIFORMITY IMPROVES, AND TO WHAT EXTENT THIS RESULTS IN IMPROVED JC, AND (5) OBTAIN INFORMATION ON HOW TO IMPROVE THE DUCTILITY OF A MATRIX CONTAINING BOTH SI AND MANGANESE. IN PHASE II, ONE OR TWO ALLOYS WHICH SHOW PROMISE WILL BE MADE INTO FULL SIZED MULTIFILAMENTARY BILLETS AND THEIR PROPERTIES DETERMINED.