The Stress Concentration Factor (K{sub}t) and Fatigue Crack Behavior on the Relative Defect Location in Monolithic Aluminum versus GLARE

摘要

To analyze the stress distribution and the crack initiation due to the location of the defects, artificial defects were made on the different locations of the high strength monolithic Al and GLAss fiber REinforced laminate (GLARE). Experimental study shows that the defect location in the vicinity of the circular hole was changed from θ{sub}4 = 90° to θ{sub}1 = 0°, the stress concentration was increased. The stress concentration of GLARE was about 15% higher than that of the monolithic Al. When the defect was at θ{sub}2 - 30°, Multi Site Damage (MSD) crack was found in the monolithic Al but not in GLARE. Instead of MSD crack, a delamination was made in GLARE and that it resulted in the prevention against the second crack initiation.