Title: Algorithm to Enhance Signal to Noise Ratio of Peel Ply at the Bondline of Out-of-Autoclave Composite Assemblies

Authors: Gary S. LeMay

DOI: 10.33599/nasampe/c.19.0760

Abstract: Out-of-autoclave materials are an established material system for secondary structural applications and are cured at reduced temperatures and pressures resulting in less compaction and homogeneity. The consequence is attenuation and extraneous ultrasonic signals during inspection. An algorithm was developed to enhance the signal to noise ratio between peel ply and the bondline in an out-of-autoclave carbon fiber reinforced polymer assembly. Peel ply is a release fabric that may be trapped between the adhesive and the substrate during the bonding process. Conventional ultrasonic testing techniques cannot consistently achieve signal to noise ratios that meet quantifiable rejection thresholds of peel ply inserts (i.e. defect representation) at each side of the bonded interface. Ultrasonic pulse echo with full waveform capture was used to inspect a representative reference standard. Waveform post acquisition analysis was used to analyze, and enhance the signal response, between the peel ply inserts and the bondline resulting in the final algorithm. To verify the results, the signal to noise ratio of each insert was calculated for both the raw and processed data.

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Conference: CAMX 2019

Publication Date: 2019/09/23

SKU: TP19-0760

Pages: 14

Price: $28.00