Accession Number : ADA303565

Title :   Nondestructive Measurement of Impact Toughness of Aircraft Windshields.

Descriptive Note : Final rept. 15 Jul 94-15 Oct 95,

Corporate Author : HOUSTON UNIV TX DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Ravi-Chandar, K.

PDF Url : ADA303565

Report Date : 15 DEC 1995

Pagination or Media Count : 38

Abstract : This report summarizes the results on the project obtained over the past fifteen months. With a view toward establishing a nondestructive procedure for evaluation - of the impact properties of polycarbonate windshield material, we have set up the following experiments (1) a split-Hopkinson bar apparatus for impact strength measurement, (1) an instrumented impact tester for impact toughness measurement and (3) a monochromator with a birefringence measuring Babinet-Soleil compensator for optical characterization. Some polycarbonate specimens have been identified as potential candidates for evaluation of the proposed method. A dynamic crack growth model based on an extension of the Dugdale-Barenblatt has been formulated and solved through a finite difference scheme. This model exhibits many of the features observed in dynamic fracture experiments. (MM)

Descriptors :   *TOUGHNESS, *IMPACT STRENGTH, *WINDSHIELDS, *AIRCRAFT CANOPIES, *THERMOPLASTIC RESINS, *POLYCARBONATES, MICROSTRUCTURE, AGING(MATERIALS), NONDESTRUCTIVE TESTING, DEGRADATION, POLYMERS, CRACKING(FRACTURING), MOLECULAR WEIGHT, TEST EQUIPMENT, STRAIN(MECHANICS), FRACTURE(MECHANICS), FINITE DIFFERENCE THEORY, CRACK PROPAGATION, BIRD STRIKES, BIREFRINGENCE, DYNAMIC TESTS, PHOTODEGRADATION.

Subject Categories : Aircraft
      Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE