Świderski, Waldemar
(Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie,
)
The main criterion for selecting materials for marine structures is the requirement of strength, which in
shipbuilding is met by steels and high strength aluminum alloys. Internal and external forces acting on the
hull of the ship have to be considered during the design process. There are also such factors as wave strength
and sea conditions, waves hitting into the bow of the ship, vibrations, thermal differences, load displacement,
loads caused by starting and landing aircraft on aircraft carriers, loads that occur upon the sudden immersion
in and emerging from water in the case of submarines, effects of fatigue, corrosion cracking, etc. Eddy
current thermography is a new non-destructive testing technique for detecting cracks in electro conductive
materials. It combines the well-established inspection techniques of eddy current testing and thermography.
The technique uses induced eddy currents to heat the sample being tested. Defects are then detected
by changes in the flow(s) of induced eddy currents, which are revealed by thermal visualization and captured
by an infrared (IR) camera. The paper discusses code for the numerical modeling of nondestructive testing by
eddy current IR thermography and of IR testing of materials used in marine structures. The ThermoEdCur
computer program developed by Vavilov was used to select suitable heating parameters of the tested metal
sheet samples in order to detect subsurface defects.