Method and device for inspecting a bond, in particular a welded joint or glued between two materials

The present invention relates to a method of inspecting a bond between two materials by the waves emitted by an ultrasonic element. The method comprises a step of injecting a viscous gel, except water, in a hollow column disposed between the connection to be inspected and the ultrasonic element, so that the waves pass between the element and the binding through the gel filling the hollow column. The present invention also relates to a sensor and an ultrasonic system to inspect a bond between two materials. Application: automotive