Analysis on the Impact of Transverse Strain on the Birefringence Coefficients

Acoustoelasticity measurement of stress based on the technology of time delay is very sensitive to small strain. In the entire load processes, small time change caused by the transverse small strain may accumulate to the time equipment which shall result in greater error to measurement. When the ultrasonic wave propagating transversely to the applied stress direction, the model of time difference to stress was set up, and the acoustic birefringence phenomena on 45 steel under tension and compression were studied by Sing-Around method. In studying on the ultrasonic wave propagation perpendicular to the stress, one model of relationship between time defense and stress was established, the experiment proved the correctness of the model. The transverse elastic strain birefringence coefficient of acoustic correction term was introduced by using the relationship of velocity both with elastic modulus and with Poisson ratio.