ABSTRACT
Hidden corrosion detection is a serious problem in many industries and in the
aerospace industry in particular. Initiating on the inside or in the interface of an aircraft's
skin, the corrosion must be tested from the outside surface. Ultrasonic bulk waves are
often used in thickness detection of plate structures by measuring the time-of-flight. An
experimental study of hidden corrosion detection by using ultrasonic non-destructive
evaluation (NDE) in the laboratory is presented. Corroded metal as well as corrosion
simulation samples were used as specimen for investigation. Normal beam probe was
used for testing and qualitative results based on the A-scan oscilloscope display
outputs were obtained.