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The damages and destructions on materials at the attachment point of an lightning arc are mainly caused by thermal effects. Pressure effects and shock waves which occur due to the high temperatures are mostly the consequence of these thermal processes. The calculation and prediction of the heating processes lead to a better understanding of the damage mechanisms. This allows the assessment and the design of materials and lightning protection components. The paper presents calculations for different materials and a critical comparison with some laboratory measurements. Investigated materials are several metals (Cu, Al, steel) on the one hand and carbon fibre composite (CFC) on the other hand. These materials differ in their electrical and thermal material parameters and in their reactions to the lightning arc stress. It was the aim of the calculations to determine the development of temperature distribution up to critical temperatures.

The temperature rise on the rear side of protected carbon fiber composite (CFC) panels caused by lightning continuing currents was determined. Painted CFC-panels with a thickness of 1, 2 and 3 mm were tested. Rectangular currents with an amplitude of 400 A and 800 A were used. The duration of the currents was varied from 20 ms to 50 ms representing the typical dwell time expected for zone 2A. Additional experiments with an exponential decaying current were carried out for comparison purposes. The temperature on the rear side of the panels was determined with a thermograph based on an infrared (IR) camera system. Arc movement and delamination at the arc root was observed with a high speed camera.