RESEARCH AND DEVELOPMENT OF NONDESTRUCTIVE TESTING TECHNIQUES FOR COMPOSITES
Abstract
Results of a research and development program relating to evaluation of nondestructive testing techniques for fiber-reinforced metallic matrix composites are reported. A bibliography, based on an extensive literature search, was compiled. Methods for continuous cleaning and inspection of boron fibers were investigated and an experimental system developed. Boron-aluminum, boron-titanium, and tungsten-copper composite specimens were fabricated with fiber volume ratios ranging from 10 to 25 percent and containing specific anomalies. Nondestructive test methods used were radiography, ultrasonics, and magnetic testing. In addition, experiments proved the feasibility of an optical method for continuous fiber surface inspection. Radiographic methods were found to be adequate to determine single fiber breaks as well as major fiber gaps and general fiber alignment. The feasibility of microradiographic inspection was demonstrated for small single layer boron composites. Ultrasonic pulse echo methods are capable of determining matrix disbonds as small as 1/4 inch square. Ultrasonic velocity measurements show a relation between velocity and fiber ratio. In addition to the experimental work, a literature survey of the problem areas was carried out and recommendations for future extensions of the work are detailed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1967
- Accession Number
- AD0815292
Entities
People
- George Martin
- John F. Moore