ASTM E 428 - 92. Standard Practice for Fabrication and Control of Steel Reference Blocks Used in Ultrasonic Inspection

American Society for Testing and Materials (ASTM). 1992, 6 pages.
This practice covers a procedure for fabrication and control of metal-alloy standard reference blocks used in ultrasonic inspection that contain flat-bottom holes (FBH) which may be used for checking performance of ultrasonic inspection instrumentation and search units and for standardization
and control of ultrasonic inspections of metal-alloy products. The reference blocks described are suitable for use with either the direct-contact or immersion pulse-echo ultrasonic inspection methods. Also described is a procedure for checking the response characteristics of the reference blocks and their relationship to materials and products being inspected