Results Obtained during Acoustic Emission Monitoring of Impact Damage Graphite/Epoxy Pressure Vessels,
Abstract
Acoustic emission (AE) sensors were used to monitor subscale graphite/epoxy pressure vessels that were subjected to increasing levels of impact damage. Impact damage was inflicted after each vessel had undergone a pressure proof test. Proof pressure is defined as 80 percent of ultimate. AE activity was then monitored throughout a series of successively higher pressure cycles ranging from 13 to 60 percent of ultimate. Each cycle included a ramp to pressure followed by a four minute hold period and pressure unload. Four sensors were used to cover the vessel surface and two additional sensors were used to monitor the impact damage site. This paper presents the AE event versus load history of these tests and demonstrates the ability of the technique to monitor the growth of damage and to estimated damage criticality (i.e. effect on ultimate strength). When significant damage was present, a noticeably higher number of events was low, indicating its insignificance to performance. The events that occurred during the pressure holds proved to be a reasonable estimator of vessel performance. Good correlations between the number of events during hold and burst pressure were obtained. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1984
- Accession Number
- ADP005008
Entities
People
- D. S. Gardiner
- K. Sakai
- M. R. Gorman
- T. H. Rytting