Acoustic Methods for Stress Measurements in Structures. Phase 1. Final Report

摘要

The Phase I SBIR investigation was performed to determine the feasibility of developing an ultrasonic/acoustic device for measuring residual stress in critical structural components. The investigation included (1) a critical review and evaluation of all stress measurement techniques reported in the open literature, (2) actual experimental residual stress measurements of welded steel plate using the critical refractive longitudinal wave (CRLW) ultrasound wave modality, and (3) the conceptual design of a state-of-the-art stress measurement system with potential for development into a field-portable design. Literature evaluation and experimental results show that the CRLW modality is most promising of all the acoustic techniques considered, and should be developed further. It is recommended that the CRLW modality be supplemented by a texture dependent ultrasonic/acoustic method such as acoustic birefringence.