Assessment of the Reliability of Phased Array NDT of Coarse Grain Component Based on Simulation

Guillemette Ribay (1) , Steve Mahaut (1) , Gérard Cattiaux (2) , Thierry Sollier (2)

1 LMC (CEA, LIST) - Laboratoire Méthodes CND (CEA, LIST)
2 IRSN/PSN-EXP/SES - Service d'Expertise des équipements et des Structures

In this paper, we present the results of a study concerning the reliability of an ultrasonic phased array inspection dedicated to cast stainless steel used in nuclear power plants. This study was performed in the framework of a collaborative project between CEA and IRSN. The methodology of determination of Probability of Detection (POD), Probability of False Alarm (PFA) and Receiver Operating Characteristic (ROC) curves is presented. First, a detailed investigation of influent parameters was performed, using both NDT engineer knowledge and literature. Then a simplified approach was used to compute POD curves in coarse grain structures without increasing computation time. It is observed that fluctuations of the metallurgic structure of cast stainless steel are the most influent factors which degrade the reliability. Prior knowledge on stainless steel grade is also recommended. PFA were then obtained using experimental data. ROC curves were also deduced from PFA and POD for several defect sizes, which could help choosing an appropriate detection threshold depending on desired inspection capabilities.

Mots clés: Human factors; Reliability

Domaines: Acoustique [physics.class-ph]

Guillemette Ribay, Steve Mahaut, Gérard Cattiaux, Thierry Sollier. Assessment of the Reliability of Phased Array NDT of Coarse Grain Component Based on Simulation. 7th European-American Workshop on Reliability of NDE, Sep 2017, Postdam, Germany. ⟨hal-04556120⟩