Acousto-Ultrasonics Nondestructive Quantification of the Damage Severity of Impact Damaged Polymer Matrix Composites
Abstract
Foreign object damage is a major concern for composite structures and a damage threat assessment in terms of residual strength loss" and detectability is a major focus in composite structural design and maintenance. Impact damage to composites, particularly under"" compression loading, reduces both residual strength and the fatigue life significantly as the damage size is increased. Due to nume""rous variables that can contribute to the damage severitysuch as material, layup, impactor geometry, energy level, boundary conditi""ons, variability of laminate response, etc., large numbers of tests must be conducted to adequately characterize effects of damage." The test matrices required for a comprehensive damage threat assessment analysis can be quite large. Previous research has shown th"e potential of acousto-ultrasonic (AUT) technique, which uses an externally generated ultrasonic source to excite stress waves and u"ses acoustic emission system to detect and analyze the propagated waves. Goal of the proposed effort is to develop an approach for quantifying the localized stiffness loss due to impact damage using acousto-ultrasonic technique that utilizes frequency-domain stress wave analysis forassessing the damage severity with a spatial map of the damage region. This technique can then be implemented as a single-sided field inspection technique for damage detection and quantification of damage severity to ensure safe operation of ai"rcraft. Once validated for impact damage, this methodology can then be expanded to detect fatigue damage, disbond, delamination and" various other anomalies that can jeopardize structural integrity. Post-impact inspections will also be conducted using standard ultrasonic and high-fidelity X-Ray CT nondestructive inspections to quantify the damage and compare against the AUT findings. Impacted" specimens then will be mechanically loaded, while acquiring full-field digital impact correlation (DIC) data for comparing the stif"fness lose and strength to demonstrate capability of AUT methodology asa field inspection technique to quantify damage severity.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 20, 2018
- Source ID
- N000141812148
Entities
People
- Waruna Seneviratne
Organizations
- Office of Naval Research
- United States Navy
- Wichita State University