Fatigue Behavior of Composite Laminates
Abstract
The main objective of this program during the final reporting period was to investigate the fatigue behavior of a (02/90/ + or - 45)s AS/3501-5A Gr/ Ep laminate through proof testing. The primary emphasis was on the delineation of the effect of proof test on the residual strength and life, the establishment of strength-life relations, and the identification of sources of scatter in strength and life. The test program consisted of static tests, tension-tension fatigue tests preceded by proof tests, and examinations of failure characteristics. Major findings can be summarized as follows: (1) Proof tests have little effect on the residual strength and life; (2) A relation exists between strength and life such that a statically stronger specimen has a longer life; (3) A minimum life can be assured by a proof test; (4) A higher modulus is an indication of a higher strength and longer life; (5) What distinguishes a typical static failure mode from a typical fatigue failure mode is the lack of delamination in the former; (6) At a moderate fatigue stress, the failure mode changes from a static failure mode to a typical fatigue failure mode around 20, 000 cycles; and (7) A delamination surface consists of shiny and dull areas. The shiny area has bare fibers whereas the dull area only has fiber traces in the epoxy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1980
- Accession Number
- ADA101349
Entities
People
- D. G. Hwang
- H. T. Hahn
Organizations
- University of Washington