Abstract:

The intended purpose of metallised nonwovens is architectural shielding against electromagnetic fields. Therefore the aim of this work was to systematically investigate the corrosion behaviour of metallic layer/polypropylene nonwoven systems in the contact with an aggressive environment (3% NaCl solution). In the work, a thermo-bonded polypropylene nonwoven was used as a substrate for CuSn and CuNiZn thin layer deposition. Nonwoven metallisation was carried out using the magnetron sputtering process. Additionally to enhance the durability of these barrier materials, their surfaces were covered with a thin, hydrophobic coating of polydimetylsiloksane. Evaluation of the corrosion resistance was made by means of potentiodynamic polarisation tests. Furthermore the degree of loss of the metallic layers was checked using a optical metallographic microscope and quantitative microanalysis by the method of Energy Dispersive X-ray Spectroscopy. It was found that the CuZnNi metallic layer deposited onto the polypropylene nonwoven shows higher corrosion resistance as compared to CuSn. In both cases, the metallic layers are the most susceptible to degradation within the nonwoven “waves”. Regardless of the layers’ chemical composition, the polydimetylsiloksane coating increases their corrosion resistance in 3% NaCl solution.