Modular, Low Cost Fixture for Evaluating OML Treatments for Stress-Strain Loading During Environmental Conditioning

ABSTRACT:Material and Process Solutions LLC will build a modular, outer mold line (OML) gap fatigue test fixture that can be used to predict the overall lifetime of a complete OML stack-ups (gap filler and coatings) used on aircraft.We will evaluate two complete OML stack-ups at three conditions: no exposure, and both sequential and concurrent environmental conditioning and fatigue testing.The modular fixture will fit into a tubular assembly that can be placed into an environmental conditioning chamber.Concurrent fatigue testing and environmental exposure is accomplished by use of the assembly.The top of the assembly has a spring and a micro motor, to impart fatigue strain of the OML treatment within the tubular assembly.This assembly is also a low cost alternative to a large mechanical test frame.BENEFIT:The benefit of this program will be to develop a set of tools and fixtures that can be used to predict of the fatigue life of outer mold line (OML) gap systems.Better prediction of OML material lifetimes will allow the DoD to procure systems that require less maintenance and support costs.The low cost tubular fatigue test assembly will also reduce the expense to test gap fillers and OML coatings.