Investigation of coatability of polymer matrix composite materials with modern coating methods

In this study, the coating properties of composite materials manufactured with pultrusion and hand lay-up methods were investigated in the coating by flame spray coating method. In the manufacturing of composite sheet profiles manufactured with pultrusion method to be coated, continuous glass fiber and polyester resin were used as matrix material. In the manufacturing of composite materials to be coated with hand lay-up method, glass fiber and 245 g/m2 carbon woven fabrics with different fiber densities (200, 300 and 500 g/m2) and epoxy resin were used as matrix material. The samples to be coated were prepared by cutting the profiles on a planer with the help of a diamond disc saw. Coating processes of Al2O3, Al2O3+TiO2, Cr2O3+SiO2+TiO2, Cr2O3+TiO2 ceramic powders were performed on plate-shaped composite materials by flame spray coating method. In order to examine the coating quality of the coated materials, samples in accordance with the standards were prepared and experiments were conducted for microstructure examinations, hardness measurements, surface roughness measurements and determination of adhesion strength values. The microstructure examinations of the samples were made with optical and SEM microscopes. The porosity amounts of the coatings were measured with the Clemex image analysis program on the optical microscope. The microhardness values of the coatings were measured with a microhardness measuring device. The adhesion strengths of the samples were determined with a tensile test device according to the ASTM C-63 standard. It was determined that the properties of the composite material on which the coating was made affected the coating quality. The highest adhesion strength value was obtained in the Al2O3+TiO2 coating made on the polyester composite material. It was observed that especially the Al2O3+TiO2 material had a significant effect on the adhesion strength in the composite material used as the coating material. The hardness values and adhesion strength values of the coatings with high porosity were low.