VIBRATORY AGING AND STRESS RELIEF (VASR) FOR A7005 ALUMINUM WELDS

THE PRIMARY OBJECTIVE OF THIS RESEARCH IS TO DEVELOP A METHOD THAT WILL IMPROVE BOTH THE RELIABILITY AND PREDICTABILITY OF WELDING AGE HARDENING ALUMINUM ALLOYS. THIS MAY BE ACCOMPLISHED BY USING AN IMPROVED VASR (VIBRATORY AGING AND STRESS RELIEF) SYSTEM, SQUARE WAVE PULSED ARC WELDING, AND POSSIBLY A COMBINATION OF BOTH TECHNIQUES. VASR TECHNIQUES INCLUDE TESTING IN BOTH THE SUBRESONANT AND RESONANT FREQUENCY LEVELS WITH ATTENTION ALSO GIVEN TO BEAT VIBRATIONS. PULSE ARC WELDING INCLUDES TESTING BOTH MICRO-PULSE MILLI-PULSE FREQUENCIES AND THE COMBINED POLY-PULSE METHOD. RESEARCH METHODS INCLUDE EMPLOYING THESE DYNAMIC TECHNIQUES IN MAKING A LARGE SERIES OF WELDS. THE RESULTS WILL THEN BE COMPARED OVER AN AGING PERIOD OF UP TO 21 DAYS, USING MICRO HARDNESS TRAVERSES AND TENSILE TESTS. MICROSTRUCTURES WILL BE EXAMINED USING TRANSMISSION ELECTRON MICROSCOPY (TEM).