Laser ultrasonics for bulk-density distribution measurement on green ceramic tiles

In this paper aLaser Ultrasonics (LUT) system is developed and applied tomeasure bulk density distribution of greenceramic tiles, which are porous materials with low heat conductivity. Bulk density of greenceramic bodies is a fundamental parameter to be kept under control in the industrial production ofceramic tiles. The LUT system proposed is based on a Nd:YAG pulsed laser for excitation and an air-coupled electro-capacitivetransducer for detection. The paper reports experimental apparent bulk-densitymeasurements on whiteceramic bodies after acalibration procedures. The performances observed are better than those previously achieved by authors using air-coupledultrasonic probes for both emission and detection, allowing to reduce average uncertainty down to about ±6 kg/m3 ( ±0.3%), thanks to the increase in excitation efficiency and lateral resolution, while maintaining potential flexibility for on-line application. Thelaser ultrasonic procedure proposed is available for both on-line and off-line application. In this last case it is possible to obtain bulk density maps with highspatial resolution by a 2D scan without interrupting the production process.

Source: Review of Scientific Instruments - October 17, 2016 Category: Physics Authors: G. M. Revel, A. Cavuto and G. Pandarese Source Type: research