Artificial Current Component A lightning strike tests were performed on three different types of composite panels. Panels of type A were not equipped with lightning strike protection; panels of types B and C were protected against lightning strike with two different types of copper mesh. The measured back surface velocity of the panels seems to be proportional to the peak current normalized with the panel weight. Post-test inspections revealed extended delamination inside panels of type A. For panels of types B and C no delamination was found. Panels of type B and C showed characteristic circular smuts on the impacted surface as well as diamond shaped evaporation of the copper mesh. For panels of type B, the dimensions of the copper evaporation were significantly larger than for panels of type C. it was also found that the orientation of the evaporation zone seems to be related to the geometry of the copper mesh. Multi-physical simulations considering the electro-explosion of the copper mesh were carried out in order to assess if the shape and extent of the evaporation zone could be traced back to electro-explosion of the copper mesh. The predicted damage correlates well with the inner damage zone, but is not able to reproduce the full amount of copper evaporation.

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In this manuscript, Current Component A lightning strike tests on three different types of carbon fiber reinforced composite panels are analyzed. The panels feature different levels of lightning strike protection: no protection, medium protection and heavy protection. In particular it was analyzed if there were any direct correlations between the peak electric current of the artificial lighting strike and the recorded velocities at the back surface of the composite panels. The existence of a master curve correlating the peak electric current, the mass of the composite panels and the measured back surface velocity was demonstrated. This finding implies that the back surface velocity correlates linearly to the inertia of the panel and the peak current of the lightning strike.

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Sensors are key elements for capturing environmental properties and are today indispensable in the industry for monitoring and control of industrial processes. Many applications are demanding for highly integrated intelligent sensors to meet the requirements on safety, clean, and energy-efficient operation, or to gain process information in the context of industry 4.0. While in many everyday objects highly integrated sensor systems are already state of the art, the situation in an industrial environment is clearly different. Frequently, the use of sensor systems is impossible due to the fact that the extreme ambient conditions of industrial processes like high operating temperatures or strong mechanical loads do not allow a reliable operation of sensitive electronic components. Eight Fraunhofer Institutes have bundled their competencies and have run the Fraunhofer Lighthouse Project "eHarsh" to overcome this situation. The project goal was to realize sensor systems for extremely harsh environments, whereby sensor systems are more than pure sensors, rather these are containing one or multiple sensing elements and integrated readout electronics. Various technologies, which are necessary for the realization of such sensor systems, have been identified, developed, and finally bundled in a technology platform. These technologies are, e.g., MEMS and ceramic-based sensors, SOI-CMOS-based integrated electronics, board assembly and laser-based joining technologies. All these developments have been accompanied by comprehensive tests, material characterization, and reliability simulations. Based on the platform, a pressure sensor for turbine applications has been realized to prove the performance of the eHarsh technology platform.