SELECTED ASPECTS OF CERAMIC COATINGS PREPARED BY THERMAL SPRAYING WITH WATER PLASMA ARC STABILIZATION

Abstract

The paper was focused on research of selected aspects of ceramic coatings prepared by thermal
spraying with water plasma arc stabilization. Before spraying, the steel substrate low carbon
steel of grade S235JRG2 was pre-treated by blasting with using the brown corundum as a
blasting media. A ceramic matrix of coating - zircon silicate was used in two types: ZrSiO4
applied by flame thermal spraying on nickel interlayer and composite of ZrSiO4 with different
addition of nickel (6, 12 and 16 wt. %). The basic characteristics of ceramic coatings were
determined by thickness and microhardness measurement. The fracture surfaces were
documented by SEM. Adhesive and abrasive properties were evaluated by pull-off adhesion test
and abrasive wear test. The results showed that the composite coatings on ZrSiO4 basis with the
addition of Ni meet the increased requirements for abrasion resistance while maintaining
sufficient adhesion. The addition of Ni to a ceramic matrix of coating improved the final
structure of coatings and it had a positive effect on the resulting adhesion. On the other hand,
with the increasing of Ni addition the microhardness values of coatings decreased.