METHOD AND APPARATUS FOR MEASURING DIAMETER DISTRIBUTION OF CRYSTAL GRAIN

摘要

PROBLEM TO BE SOLVED: To provide a method and an apparatus, capable of high precision measurement of the diameter distribution of crystal grains, even if the measurable frequency band of ultrasonic waves is restricted.;SOLUTION: Ultrasonic waves are generated in an object to be measured made of a polycrystalline material, and attenuation factor of the ultrasonic waves is measured, to acquire observed attenuation factor. The attenuation factor of ultrasonic waves is theoretically computed, on the basis of an assumed diameter distribution of crystal grains to acquire the theoretical attenuation factor. The observed attenuation factor is compared with the theoretical attenuation factor, and the diameter distribution of crystal grains of the object to be measured is determined based on the comparison results.;COPYRIGHT: (C)2006,JPO&NCIPI