Evaluation of Clutch Plate Integrity with Non-Destructive Methods

Abstract Nondestructive evaluation (NDE) represents an important phase in the life cycle of a product to detect defects both in service and in production. NDE techniques most commonly used to detect surface defects are visual inspection and methods based on eddy current and ultrasound. Laser and non-contact sensors have been recently used to inspect ultrasonically without contact. Components with complex geometry are usually inspected combining several NDE techniques, or simply visually where analysis and evaluation of results are performed by an operator based on specific parameters of acceptance. This last method is currently used to inspect the clutch plates since their complex geometry, for the presence of grooves, limits the use of other methods. This work shows the possibility of using a non-contact ultrasonic technique and guided waves (Lamb) to detect surface defects in clutch plates. An appropriate source/receiver configuration allows to overcome the limitations due to the complexity of the geometry. This technique allows, compared to the visual inspection, to detect smaller and internal defects, and to obtain objective results, not depending on the evaluation of the operator. The inspection method can be very fast and applicable in the production line by using a fully automated control system.