ULTRASONIC SENSOR FOR INTERNAL FLAW DETECTING IN METALS

摘要

The present invention relates an ultrasonic sensor for detecting inner scratch of a metal material such as a steel billet which is manufactured in a timber factory of an iron mill by a non-breakdown method. It is an object to provide an ultrasonic sensor having a good bond absorption efficiency to various generating signals by dispersing a piezoelectric element into a sound absorption layer. The ultrasonic sensor includes a sound absorption layer(50) which is composed of an epoxy more than 15 wt% and a piezoelectric element powder more than 85 wt%; or an epoxy more than 15 wt%, a piezoelectric element powder less than 83 wt%, and a tungsten powder more than 2 wt%.