Accession Number : AD0746592
Title : Development of Nondestructive Test Techniques for Multidirectional Fiber-Reinforced Resin Matrix Composites.
Descriptive Note : Final rept. Jun 69-Jun 71,
Corporate Author : MCDONNELL DOUGLAS ASTRONAUTICS CO-WEST SANTA MONICA CALIF
Personal Author(s) : Cook,John L. ; Reinhardt,Walter W. ; Zimmer,James E.
Report Date : OCT 1971
Pagination or Media Count : 213
Abstract : The second year of effort of a two-year program was devoted to the study of the applicability of nondestructive analysis to the B-stage condition composite, evaluation of cured composite variability, relation of composite mechanical strength to location and severity of weave irregularities, and evaluation of the material elastic constants by means of ultrasonic velocity measurements verified through mechanical load versus strain data. The application of the ultrasonic attenuation C-scan mapping technique did not enable discrete areas of altered impregnation to be clearly detected. Both C-scan attenuation and ultrasonic velocity measurements were indicative of composite variability in the fully cured condition. Application of film radiography and ultrasonic attenuation measurements to an orthogonal construction frustum indicated that these techniques were feasible for inspection of such surfaces of revolution. Mechanical tests showed that tensile values were most seriously affected by weave defects or irregularities. While not all irregularities resulted in loss of strength, most failures were located at some weave defect. It was found that in-plane properties could not be accurately predicted from through-the-plane nondestructive measurements. Both ultrasonic C-scan attenuation and longitudinal and shear wave velocity measurements have been used to assess material variability and to predict elastic constants. (Author-PL)
Descriptors : (*REINFORCED PLASTICS, *NONDESTRUCTIVE TESTING), (*COMPOSITE MATERIALS, NONDESTRUCTIVE TESTING), ULTRASONIC RADIATION, RADIOGRAPHY, TEXTILES, QUARTZ, AGING(MATERIALS), MECHANICAL PROPERTIES, TENSILE PROPERTIES, FAILURE(MECHANICS), ATTENUATION, QUALITY CONTROL
Subject Categories : Laminates and Composite Materials
Distribution Statement : APPROVED FOR PUBLIC RELEASE