LAUSR

Abstract Monitoring the stiffness of adhesives is a crucial issue when considering the durability and strength of adhesive joints. While there are many studies conducted on specimens made only from adhesive, the problem of curing of an adhesive film in real joints is moderately considered. This paper presents the monitoring of stiffening of epoxy adhesive using ultrasound. Ultrasonic pulse velocity method was firstly applied for monitoring of adhesive specimens. Then, a new procedure using dispersion relations and scanning laser vibrometry was proposed for monitoring the curing process of an adhesive joint of steel plates. Both approaches gave comparable results showing the increase of the dynamic elastic modulus of adhesive in time. The study presented that the proposed procedure was capable of real-time monitoring the curing process of an adhesive layer in multi-layer systems.