Annual Summary Report for ONR Contract Number N00014-81-K-0011, Investigation from November 1984 to the Present.
Abstract
This investigation is aimed at studying acoustic emission for applications to residual stress measurements and for the evaluation of structural integrity of engineering structures. Effects of microstructure, composition and prior cold working on magnetomechanical acoustic emission (MAE) have been studied. Magnetization behavior, magnetostriction and Barkhausen noise are affected by stress as well as other parameters. These responses will be measured simultaneously in order to identify the the stress level uniquely. Combinations of advanced signal analysis methods at present, and have been studied to identify the optimum parameters for applications. In the second part of this study, acoustic emission from materials undergoing plastic deformation and fracture has been examined in an attempt to improve detection capability of the impending structural failure. Our previously established techniques are extended in studying the acoustic emission behavior of advanced aluminum alloys and composite materials. Digital signal analysis techniques are used to investigate further the different types of acoustic emission signals from various sources. A major emphasis has been placed on the fracture related AE in high strength aluminum-lithium alloys and fiber-reinforced advanced composites including metal matrix (Al-SiC) and resin matrix (graphite-epoxy) materials.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1985
- Accession Number
- ADA159899
Entities
People
- K. Ono
Organizations
- University of California, Los Angeles