Ultrasonic Properties of IIW Type Reference Blocks, Part 2: Variability of Angle Beam Response

A series of measurements was made on 18 ferromagnetic steel IIW type reference blocks to determine the amount of variation in the ultrasonic properties of the blocks. In this paper, we focus on standardization measurements typically performed with angle beam search units. Exit point and angle of refraction measurements were made to illustrate the practical effects of any variations in the primary ultrasonic properties (elastic wave velocities and attenuations) of the blocks. The measurements of the primary ultrasonic properties of this sample of reference blocks were discussed in "Part 1: Measurements of Primary Properties" in Materials Evaluation, September 2000, Vol. 58, No. 9, p 1075. Here, the different measurement methods and uncertainties affecting the standardization measurements are discussed. Relatively little variation was found in the exit point and angle of refraction measurements. While we were able to detect significant variations in some of the primary ultrasonic properties (elastic wave velocities) of the sample of blocks, the range of these variations does not significantly affect the primary standardization uses of these blocks.