Evaluation of nondestructive evaluation techniques for determination of flawed conditions and the effects of flaws on the burst pressure in Kevlar-epoxy filament-wound spherical test specimens

Technical Report · Fri Dec 01 00:00:00 EST 1989

OSTI ID:6878975

Brosey, W D; Calfee, M T; Whittaker, J W; Waldrop, D A ^[1]; Henneke, E G; Post, D; Reifsnider, K L ^[2]; Blake, R A ^[3]

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1. Oak Ridge Y-12 Plant, TN (USA)
2. Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (USA)
3. Delaware Univ., Newark, DE (USA)

A study of nondestructive evaluation techniques on spherical filament-wound Kevlar-epoxy test specimens has been performed, and the results are presented. The objectives of the study were (1) to determine the sensitivity of several NDE techniques for the detection of a series of flaw conditions in an enclosed geometry and (2) to determine which flaw conditions affected the mechanical strength of the composite specimens. Seventy spherical specimens were made. Ten of the specimens contained one of seven defect conditions which simulated manufacturing or handling defects. Defect conditions involving delaminations, voids, inclusions, loss of fiber, loss of matrix, reduced fiber modulus, or matrix cracking were readily detectable with one or more inspection techniques. Specimens with fiber tension variation could not be distinguished from standard no-defect specimens with the inspection techniques used in this study. It was found that nominal defects introduced during the manufacturing or handling process do not significantly reduce the ultimate burst strength of the composite material in this geometry; however, impact damage was found to significantly affect burst pressure and location. Acousto-ultrasonic and acoustic emission techniques were found to be predictive of burst pressure for specimens with a normal matrix. Low-epoxy matrix specimens were found to sustain more damage for a given impact energy than specimens containing a normal matrix. 23 refs., 3 tabs.

• Research Organization: Oak Ridge Y-12 Plant, TN (USA)
• Sponsoring Organization: DOE/DP
• DOE Contract Number: AC05-84OS21400
• OSTI ID: 6878975
• Report Number(s): Y-2428; ON: DE90014839
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
36 MATERIALS SCIENCE
99 GENERAL AND MISCELLANEOUS//MATHEMATICS, COMPUTING, AND INFORMATION SCIENCE
COMPOSITE MATERIALS
DEFECTS
NONDESTRUCTIVE TESTING
CAT SCANNING
CERAMICS
COATINGS
COMPUTER GRAPHICS
COMPUTERIZED CONTROL SYSTEMS
DAMAGE
ELECTRIC COILS
EPOXIDES
EVALUATION
FLOWSHEETS
IMAGES
IMPACT SHOCK
INSPECTION
MEASURING METHODS
OPTICAL PROPERTIES
PRESSURE EFFECTS
SAMPLING
SENSITIVITY
THERMOGRAPHY
THREE-DIMENSIONAL CALCULATIONS
TOMOGRAPHY
ULTRASONIC TESTING
VARIATIONS
X RADIATION
Y-12 PLANT
ACOUSTIC TESTING
COMPUTERIZED TOMOGRAPHY
CONTROL SYSTEMS
DIAGNOSTIC TECHNIQUES
DIAGRAMS
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
EQUIPMENT
IONIZING RADIATIONS
MATERIALS
MATERIALS TESTING
NATIONAL ORGANIZATIONS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
RADIATIONS
TESTING
US AEC
US DOE
US ERDA
US ORGANIZATIONS
420500* - Engineering- Materials Testing
360603 - Materials- Properties
990200 - Mathematics & Computers