Nonlinear ultrasonic imaging in complex media: Aging of material and preservation of cultural heritage

The preservation of patrimonial is an interdisciplinary challenge which needing the expertise of many scientific disciplines as well as chemistry, physic, historical, etc. In order to generalize the idea of protection, Non Destructive Testing (NDT) is necessary for cultural heritage protection. The Loire Valley in France has a diversified cultural heritage, including monuments where the mainly construction units is stone. Research has been undertaken to determine the potential of Nonlinear Time Reversal (TR) non destructive techniques in symbiosis with classical FTIR and X-ray chemical analysis for revealing the aging and chemical composition of historic stones. It is shown that the sensitivity of TR based nonlinear ultrasonic methods in symbiosis with high frequency FTIR methods reaches the level of sensitivity for future non-invasive ultrasonic methods applied to cultural heritage.