THZ Imaging for Nondestructive Evaluation of Coated Metallic Surfaces of Naval Systems
Abstract
Structural deficiencies and subsequent repairs significantly contribute to the late completion of submarines and ship availabilities, resulting in a reduced deployment capability. Using terahertz real-time imaging to nondestructively identify structural defects could significantly reduce maintenance down time. This research investigates the possibility of using terahertz to perform nondestructive evaluation on coated surfaces of naval vessels and other systems. The Navy's THz studies, including current capabilities, are surveyed and analyzed. Theoretical aspects of THz properties of materials are studied on the framework of nondestructive evaluation. Leveraging real time, high resolution imaging to identify small surface defects, a Microxcam-384i camera in combination with a THz illumination source emitting at 0.5 THz was used to perform several tests. The ability to detect abnormalities on the coated metal surfaces such as air and water pockets, corrosion, cracks, and wrinkle without removing the coating was accessed. This study shows that many coatings used in naval systems are suitable for real-time imaging nondestructive evaluation, and defects such as cracks, corrosion, wrinkle, and water pockets can be detected without the removal of the coating. Preliminary results indicate that there are many opportunities for improvement and identification of specific characteristics of imaging systems required for different coatings.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2022
- Accession Number
- AD1214328
Entities
People
- Keith L. Gibson
Organizations
- Naval Postgraduate School