Research Engineer, Boeing Commercial Airplane Company, Seattle, Wash
Professor, Virginia Polytechnic Institute and State University, Blacksburg, Va.
Pages: 18 Published: Jan 1982
Quasi-static response and fatigue response under tension-tension loading, R = 0.1, to 106 cycles were evaluated for two laminate types. (±45/0)s and (90/0)s, of T300-5208. All laminates contained a longitudinal notch embedded in the 0-deg plies. Results were compared with previous fatigue studies of the same laminates with a transverse notch embedded in the 0-deg plies. Nondestructive investigation methods used to evaluate damage included acoustic emission, ultrasonic attenuation, C-scan, soft X-radiography, thermography, and stiffness change. Results show that damage initiation and growth depend more on laminate type than on notch orientation. Constraining plies of ±45 deg provided better interfiber splitting resistance and delamination resistance than constraining plies of 90 deg. All nondestructive investigation techniques showed good correlation throughout the testing.
composite materials, fatigue, nondestructive tests, radiography, acoustic emission, C-scan, stiffness change
Paper ID: STP28487S