Papers by Author: Danuta Kotnarowska

Abstract: The paper presents investigation results of climatic as well as environmental factors influence on surface state of three-layer epoxy coatings. A three-year investigation documented substantial destruction of coating surface layers. In particular, a significant increase of aged coating surface roughness, evaluated on the basis of Ra and Rz parameters, was observed. Studies made with SEM corroborated a delamination as well as pigment and filler crumbling from surface layers of coatings. In the final period of ageing craters and superficial cracks appeared in the coating structure. Destruction of aged coating surfaces contributed to their gloss loss by over 98% (for light incidence angle α = 60^o) decreasing in this way coating decorative properties.

Abstract: The paper deals with experimental investigation of erosive wear of acrylic coating. The research was carried out on the erosive wear under the influence of alundum particles (grain size of 0.6 – 0.7 mm) striking the coatings at the angle of 45 degrees. It was established that intensity of the erosive wear (under the influence of free falling alundum particles) essentially depends on velocity of erosive particle at the moment of its impact against coating surface. For example, for the lowest velocity value (3.6 m/s) at the moment of impact, erosive wear intensity was equal to 0.4 mm/kg, while for the largest velocity value (5.3 m/s), the intensity doubled in magnitude. The characteristic of erosive wear intensity, depending on erosive particle velocity, was generated by using second-degree polynomial.

Abstract: The paper presents results of investigation on physico-chemical (among others – mechanical) properties of epoxy coatings subjected to the ageing with ultraviolet radiation and such aggressive media as 20% aqueous solutions of: sodium chloride, potassium hydroxide and sulfuric acid (for 1080 h).

Abstract: The paper presents results of investigation of the influence of copper nanoparticles (of mean diameter 66 nm and mass share – 3.5%) on erosive wear of acrylic coatings. It was demonstrated that addition of copper nanoparticles increased the erosive wear resistance of modified coatings in the range from 25% for impact angle of α = 30° to 65% for α = 75° on the average.

Abstract: The paper presents examination results of erosive resistance of epoxy coatings as well as epoxy coatings with interlayer modified by glass microspheres after ageing under the influence of ultraviolet radiation. Glass microspheres used as filler are spherical particles of aluminosilicate, filled with carbon dioxide and nitrogen, of a diameter not exceeding 0.03 mm and their mass share in the interlayer is 10 %.