ON-LINE DAMAGE MONITORING AND EVALUATION IN CFRP AEROSPACE STRUCTURES DURING MECHANICAL TESTING

摘要

Mechanical testing of aeronautic composite structures comprise the evaluation of damage evolution by NDT methods, like ultrasonics. Usually, scheduled inspections are performed during fatigue testing in order to assess damage progress. Registers are obtained during test stops and recorded directly on part or C-Scan file if feasible (complex geometries, no access for encoders, etc.). In case of static testing, in-live thermographic inspections can be performed for detection of fiber breakages and/or appearance of delaminations. Data storage results a difficult task during fatigue testing since test execution period comprise several months. The aim of this study is to develop an innovative Non-Destructive Testing (NDT) system for on-line monitoring of composite aircraft components during fatigue mechanical tests execution. A feasibility test campaign including different NDT methods (Air coupled Ultrasonics, Wheel Probe Ultrasonic phased Array, Thermography...) has been performed. Once NDT method is selected, the conceptual approach of the system has been evaluated during mechanical testing of large composite panels, including system geometrical configuration, data analysis, automatic detection of damage event and data storage, etc. Finally, a conceptual system for CFRP cockpit evaluation is presented.