Analysis of the plane stress state by combined ultrasonic waves

This study investigates the measurement of the residual stress state in ASTM A131 steel plates using a non-destructive technique based on the combination of ultrasonic waves. The method combines shear and compressive waves to more accurately assess the stress state of the material after heat application via TIG welding. Measurements were taken at different points on the plate using transducers attached to a stepper motor, which enabled the rotation of the transducer and precise determination of the wave propagation angle. The results showed that residual stresses were more concentrated near the weld zone and the supports that held the sample, while areas farther away showed significantly lower stresses. The technique proved effective in measuring the residual stress state, overcoming the limitations of traditional methods, which often estimate only the differences between principal stresses. This approach has the potential to be applied in various industries, particularly in sectors that require accurate stress evaluations in structural components, such as naval construction. The combined use of shear and compressive waves offers a non-destructive and highly precise alternative to ensure the integrity and durability of materials.