Transducer, device and method for monitoring integrity of an adhesive bond

A method of monitoring integrity of an adhesive bond between a first element and a second element, the method comprising the steps of:

• (a) generating at least one of a first acoustic signal and a second acoustic signal;
• (b) passing the at least one of the first acoustic signal and the second acoustic signal through the adhesive bond;
• (c) receiving the at least one of the first acoustic signal and the second acoustic signal that has passed through the adhesive bond;
• and
• (d) comparing the at least one of the first acoustic signal and the second acoustic signal that has passed through the adhesive bond with a predetermined reference signal;
• at least one of step (a) and step (c) being performed by a transducing adhesive, the transducing adhesive provided in a transducer, the transducer comprising:
• the transducing adhesive provide to act as at least one of:
• an actuator to convert a first electrical signal to the first acoustic signal, and
• a sensor to convert the second acoustic signal to a second electrical signal
• the transducing adhesive comprising:
• (i) an adhesive inherently having a piezoelectric effect,
• (ii) a mixture of an epoxy adhesive and a lead-free piezoelectric ceramic particles, or
• (iii) a combination of (i) and (ii);
• and
• an electrode provided on the transducing adhesive, the electrode provide to perform at least one of:
• providing a third electrical signal to the transducing adhesive, and
• receiving a fourth electrical signal from the transducing adhesive,
• the first acoustic signal being the same as or different from the second acoustic signal, the first electrical signal being the same as or different from the second electrical signal, the third electrical signal, or the fourth electrical signal, the second electrical signal being the same as or different from the third electrical signal or the fourth electrical signal, the third electrical signal being the same as or different from the fourth electrical signal,
• the transducer being at least partially provided in the adhesive bond between the first element and the second element, at least one of the first acoustic signal and the second acoustic signal being passed through the adhesive bond.