THE DEVELOPMENT OF PROCESSING TO PRODUCE FINE PARTICLE ALUMINUM WITH A PASSIVE COATING OF ALF3

THE HEATS OF DETONATION OF ALUMINIZED EXPLOSIVES AND PROPELLANTS ARE, IN GENERAL, CONSIDERABLY HIGHER THAN FOR NON ALUMINIZED MATERIALS. HOWEVER, THE INHERENT OXIDE ON THE ALUMINUM INTERFERES WITH AND DELAYS THE DETONATION PROCESS. IT IS POSSIBLE THAT THE SUBSTITUTION OF A FLUORIDE (ALF3) COATING FOR THE OXIDE IN THE PRODUCTION OF THE ALUMINUM POWDERS WOULD LEAD TO EARLIER PARTICIPATION OF THE ALUMINUM IN THE DETONATION. A PROCESS IS PROPOSED THAT IN-SITU PRODUCES ANALF3 COATING ON SPHERICAL SHAPED ALUMINUM PARTICLES WHICH FORMS A PASSIVE FILM TO OXIDATION. TO AVOID PRODUCING ALF3 PARTICLES AND THE SUBLIMATION OF AN ALF3 COATING, WHICH OCCURS AT 1291 DEGREES C, IT ISNECESSARY TO CONDENSE ALUMINUM IN THE ABSENCE OF A FLUORINE ATMOSPHERE AND REACT THE FLUORINE WITH ALUMINUM PARTICLES BELOW THE ALF3 SUBLIMATION TEMPERATURE. THIS PROGRAM WILL DEVELOP AND DEMONSTRATE PROCESSING TO PRODUCE A PASSIVE ALF3 FILM ON ALUMINUM PARTICLESAND CHARACTERIZE AS TO ALF3 THICKNESS, PERFECTION AND STABILITY OF THE COATING IN THE PRESENCE OF MOISTURE FOLLOWED BY DELIVERY OF SAMPLES TO THE NAVY.