Patent ID: 8499633
Filing Date: 2013-08-06
Classification: G01N

Abstract:
1. A method of detecting internal discontinuities or inhomogeneities in a green or fired ceramic honeycomb structure having an inlet end and an outlet end, wherein said ceramic honeycomb structure has passageways of air and passageways of substrate that define cell walls between said inlet and outlet ends, comprising the steps of: positioning an ultrasonic transmitter adjacent to but not in contact with one of the inlet end and outlet end of the honeycomb structure, actuating the ultrasonic transmitter to propagate an ultrasonic wave of between about 150 KHz and 700 KHz into said passageways in the honeycomb structure, receiving a response of the propagated ultrasonic wave as modulated by the structure by an ultrasonic receiver positioned opposite the ultrasonic transmitter, moving said ceramic honeycomb structure relative to said ultrasonic transmitter and said ultrasonic receiver to scan said passageways, and analyzing the response of the propagated ultrasonic wave to detect said internal discontinuities or inhomogeneities in said honeycomb structure, wherein said received response includes a distance through air signal (DTA) and a distance through substrate signal (DTS), and further comprising the step of selecting one of said DTA signal or said DTS signal to detect said internal discontinuities or inhomogeneities.