STRUCTURAL PROPERTIES OF SOLID PROPELLANTS

DESIGN OF HIGH ACCELERATION MISSILES FOR AIR FORCE MISSIONS REQUIRES METHODS OF INCREASING THE STRUCTURAL STRENGTH OF SOLID PROPELLANTS TO PROVIDE GREATER LOAD CARRYING CAPACITY OF THE TOTAL MISSILE. HIGH ACCELERATION INCREASES THE FORCES ON THE SOLID PROPELLANT GRAIN CAUSING THE GRAIN TO SLUMP OR DEFORM. IN ADDITION TO INCREASING STRUCTURAL PARAMETERS, IT IS DESIRABLE TO INCREASE THE PROPELLANT'S BURNING RATE AND SPECIFIC IMPULSE. MATERIALS LIKE ALUMINUM, BORON, BERYLLIUM, ZIRCONIUM, TITANIUM AND MAGNESIUM HAVE BEEN ADDED TO SOLID PROPELLANTS TO IMPROVE SPECIFIC IMPULSE. USUALLY THESE METALS HAVE BEEN ADDED IN POWDER FORM, BUT IT IS POSSIBLE TO USE FIBERS, WIRES, FOILS AND SCREENS OF THESE MATERIALS TO ENHANCE STRENGTH, PERFORMANCE AND BURNING RATE. THE PHASE I STUDY WILL DEFINE THE LIMITS OF STRUCTURAL ENHANCEMENT POSSIBLE AND THE LOADS INDUCED BY VARIOUS MISSION PROFILES. PHASE II WILL DEVELOP ANALYTICAL AND EXPERIMENTAL RESULTS FOR THE MOST PROMING CONCEPTS. THE UNITED TECHNOLOGIES CORPORATION HAS AGREED TO WORK WITH BELTRAN ON THE PHASE II PROGRAM, WHERE FORMULATION AND FABRICATION OF SOLID PROPELLANT MAY BE REQUIRED. THIS PROGRAM IS AVAILABLE FOR THE NEW YORK STATE FUND MATCHING PROGRAM WHERE THE FUNDING AGENCY CAN DOUBLE THE R&D WITHOUT EXPENDING FUNDS ABOVE THE ORIGINAL SBIR CONTRACT.