An acoustic method of fault-detection in ceramic lining plates

The paper contains a general description of an acoustic measuring method, as well as of an electroacoustic measuring equipment designed for current quality tests of ceramic lining plates to be used in the building industry. The method is based on the physical relations, which exist between the acoustical parameters of the plate excited in mechanical vibration and its structural and mechanical properties.

It has been found that the distinctive feature, which may be used to recognize the defective plates, is the ratio of a few resonance frequencies corresponding to characteristic modes of vibrations. Similarly, plates with invisible structural defects may be detected by the measurement of the absolute value of a selected resonance frequency.

According to these rules, an experimental measuring equipment has been designed, constructed and evaluated. A new improved model will be subjected to detailed exploitation tests under normal production conditions in manufacture.