Method for inspecting an object, in particular a welded joint or glued between two materials

The present invention relates to a method of inspecting an object by waves transmitted from at least one ultrasonic element. The method comprises a step of injecting a viscous gel in a hollow column arranged between the object to be inspected and the ultrasonic element, so that the waves pass between the member and the object through the gel filling the hollow column. The injection step includes: - transmitting the sound waves from the element to the object; - receiving at the element the echoes of said waves on the surface of the object; - measuring a characteristic value of said echoes; gel of the injection being interrupted as soon as the characteristic value reaches an initial local maximum. Application: automotive, boiler, aviation, naval, furniture, railways, household appliances