Investigations of Wettability of Wear Resistant Coatings Produced by Atmospheric Plasma Spraying

摘要

Changes in fluids contact angle in the interaction with materials surface can play a critical role in enhancement of hydro-machine components and pipelines efficiency and/or service lifetime. However most nowadays used materials and/or coatings are made from polymers or ceramic polymer composites produced by highly sophisticated and/or very expensive techniques. Unfortunately there are a lack of mechanical properties. With the aim to study the role of the surface topography on the water contact angle changes, the representatives of wear resistant coatings (WC10Co4Cr, Cr_2O_3+5SiO_2+3TiO_2 and Al_2O_3) were produced by means of atmospheric plasma spraying. Wettability of the coatings surface was studied by adding the liquid droplet on as sprayed, grinded and polished coating's surface by measuring the changes of its contact angle. To estimate the coatings phase composition and topography XRD technique and optical profilometer were used. The contact angle of water was measured by sessile droplet method. To obtain the complex information of the cross-sectional coatings microstructure the conventional metallographic analysis approaches and optical microscopy were also used.