NiCr Electrically Conductive Coatings on Cotton Fabric by Electron Beam Evaporated Deposition

Abstract

The 80Ni20Cr coatings on cotton fabric substrates using the electron beam evaporated deposition are reported to improve the electrical conductivity of fabric substrates. The cotton fabrics are coated twice for single-faced NiCr film and one time per face for double-faced NiCr film, respectively. The morphology of coatings is characterized by an optical microscopy. The effect of sample length and test orientation of warp-wise and weft-wise on electrical conductivity is measured. It is found that the NiCr coatings dramatically increase the electrical conductivity of cotton fabrics. For warp-wise orientation with lengthwidth (4 cm1 cm) of test sample, the surface resistance is about 0.7 MΩ for single-faced coating and 0.89 MΩ for double-faced coating, while the surface resistance of raw cotton fabric is above 104 MΩ. The results tested from warp-wise and weft-wise are uniform, which is mainly because of the structure balance of the plain fabrics. The microstructure observation indicates that the single-faced coatings are uniform and dense, and the present double-faced coating processes are not enough to completely cover the fabric substrates. The uniform and dense coatings of single-faced NiCr coatings could be the reason that the electrical conductivity is better than that of the present double-faced NiCr coating.