Measurement of Acoustoelastic Constant in Iron-Base Alloy Based on Acoustoelasticity Theory for Stress Evaluation

This study aims to investigate the ability of ultrasonic method by using critically refracted longitudinal (LCR) wave for measuring stress in the elastic phase of an iron-base alloy and a an equation includes of  acoustoelastic constant was provided. For this purpose, extract detail of metal alloy components was achieved by use of quantometer analysis testing and . In order to send and receive the LCR wave into the samples, the investigation leads to design a unique type of ultrasonic fixture. The fixture was made based on Snell’s law that only in one part. In the next step, different amounts of stress were applied to the specimens by using a uniaxial tensile testing machine and record stress-strain curve data. To this end, more than three metal samples were used in the study. Measurement of longitudinal applied stress by ultrasonic method was done by using 2MHz probes based on Acoustoelasticity theory and close to the surface of the samples. After conducting the experimental tests, the results indicated that there was a significant relation between stress and time of flight and wave speed in the elastic phase of the used sample. Every material has a unique acoustoelastic constant that can determine stress value by having times of flight wave. The conclusions of the study provide a gradient of a line that known as an acoustoelastic constant. Finally, by comparing the results of the used method with other researchers results, findings showed that there were good agreements between them which shows the good capability of acoustoelasticity theory in the measurement of stress.