Characterization of Metal/Ceramic Interfaces in Dental Materials by Acoustic Emission

Porcelain fused to metal (PFM) is one of the more extended combined rigid restoration devices used in dental materials. PFM combines good mechanical properties of metals and aesthetic properties of ceramics. The quality of those parts depends on metal/ceramic interface, throughout factors like adhesion. There are different methods that evaluate the metal/ceramic bond, some of those are standardized. The aim of this work is to apply the Acoustic Emission technique (AE) in the characterization of metal/ceramic interfaces under the action of a charge. Elastic waves produced in any material when it is submitted to forces, are known as AE. To assess the material behavior, the waves are detected by piezoelectric sensors. In this research, the metal/ceramic bond was studied by a flexural test of three points. The results of the AE parameters were correlated with surface and heat treatment performed on the substrates. These changes affect metal-ceramic adhesion.