Effect of Surface Preparation on Fatigue Durability of Bonded Composite Repair Patches. Volume 6 - Delivery Order 4, Task 1
Abstract
A test program was conducted to investigate two issues: (a) Whether fatigue testing could discriminate between optimum and inferior surface preparations. (b) Whether a correlation exists between wedge and fatigue test results. Wedge and fatigue specimens were prepared with two surface preparations. One was considered to be highly durable and one to have poor durability in hot-wet environments. The highly durable preparation involved a Grit-Blast Silane (GBS) surface treatment with BR127 primer. The poor durability preparation consisted of Scuff Sanding (55) with no primer. The fatigue specimens consisted of an aluminum panel with a bonded boron/epoxy composite patch. The wedge specimens behaved as expected, with the GBS/BR127 surface preparation exhibiting low-crack growth and cohesive failure while the SS/no primer surface preparation exhibited high-crack growth and interfacial failure. The fatigue performance was quantified by obtaining periodic C-scans during the tests and determining the percentage of the patch bond area that was degraded as fatigue cycling progressed. Comparison of these C-scan results, as well as failure modes, with the wedge test results, indicated that there was relatively good correlation between wedge and fatigue behavior for the two extremes of surface preparation investigated here.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1999
- Accession Number
- ADA400387
Entities
People
- D. R. Askins
Organizations
- University of Dayton