ULTRASONIC MEASUREMENT OF RESIDUAL-STRESSES UNDER INDUSTRIAL CONDITIONS

Ultrasonic measurements were made on a set of steel products including cylindrical forgings, railroad rails and railroad solid wheels, using surface skimming longitudinal waves, critically refracted shear waves polarized in vertical (SV) and horizontal (SH) directions to the surface and bulk SH waves. The time of flight data are related to the stresses existing in the material of the items under test. The distribution of residual stresses in the near-to-the-surface layer of cylindrical forgings and railroad rails is presented. Possibilities of ultrasonic measurement of thermal longitudinal forces in continuously welded rails are discussed. The development of hoop residual stress in the rim of a railroad rim during severe braking is reported.