Development of Highly Wear Resistant Coatings for Deflector Blades in Paper Industry

Abstract

In the sieve section of a paper producing machine, where the formation of paper occurs, a polyethylene sieve is guided over a set of ceramic blades to remove the water in the paper slurry. These sieves are running with velocities of 70 km/h and more. The high velocities lead to defects in the tissue structure of the sieve as well as on the blades. Moreover the presence of high abrasive particles like kaolin and carbonates in the paper slurry as well as its corrosive characteristics enforce the material wear. Present solutions include bulk ceramic blades but they cause defects on the sieves and they are quite expensive. New solutions are desired where these bulk ceramic blades can be replaced by intelligent coating systems that on one hand exhibit an extraordinarily high wear resistance but can minimize the wear of the PE sieve on the other hand. The presentation gives first results obtained by different types of ceramic and cermetic coating systems manufactured by thermal spray technology.