LOW THERMAL EXPANSION METAL COMPOSITE JOINTS FOR SPACE STRUCTURES

GRAPHITE/MAGNESIUM COMPOSITES ARE IDEAL FRO SPACE STRUCTURESBECAUSE OF THEIR LOW CTE, HIGH STIFFNESS AND STRENGTH, LOW DENSITY, AND LACK OF OUTGASSING OR MOISTURE ASORPTION. ALTHOUGH THESE MATERIALS ARE BEING FABRICATED INTO LONG STRAIGHT SECTIONS, NO METHOD HAS BEEN AVAILABLE TO JOIN THESE SECTIONS USING A SIMILAR MATERIAL TO FORM A COMPLETE STRUCTURE. RECENTLY DEVELOPED IS A NEW TECHNOLOGY WHICH ALLOWS GRAPHITE/MAGNESIUM COMPOSITES TO BE DIRECTLY CAST. THIS TECHNOLOGY IS ADAPTABLE TO PRODUCING LOW CTE JOINTS HAVING THE NECESSARY COMPLEXITY IN SHAPE AND FIBER ORIENTATION FOR THIS APPLICATION. THE PURPOSE OF THIS PROGRAM IS TO DESIGN, PRODUCE, AND TEST SUCH JOINT STRUCTURES. PHASE I IS DEVOTED TO SIMPLE CONFIGURATIONS. ANALYSIS OF THESE PRODUCTS PROVIDES GUIDE-LINES FOR DESIGN AND FABRICATION OF MORE COMPLEX JOINT STRUCTURES IN PHASE II.