Comparative study of Pulsed IR Thermography and Ultrasonic Testing to obtain a porosity mapping of oxide/oxide CMC specimens

Abstract

In this paper, a Non Destructive Testing approach by active infrared thermography is used to investigate porosity in oxide/oxide CMC specimens. In this study, an experimental bench is developed using pulsed thermography in reflection or transmission modes coupled with transient heat transfer modelling in order to detect inhomogeneities. Results obtained are discussed and compared to ultrasonic testing which is commonly used in Non Destructive Tests.

Detection of manufacturing defects in ceramic matrix composite (CMCs) by using the active thermography

“…In the latest investigations which had been made [1], two halogen lamps whit 6 kJ each are used to provide the thermal solicitation to the sample. The surface of the specimen is preliminary painted to have an emissivity close to 0.97.…”

“…In this work, pulsed IR thermography which is a conventional non-destructive testing approach that offers many advantages (a rapid measurement, simple set-up...) has been proposed. A porosity map and an estimation of the porosity rate by correlating the temperature and the porosity distribution has been obtained [1]. The objective is now to go further and analyze the presence of macropores that are defined as a pore with a size of 10-100 µm.…”