Abstract
Anilox rolls are ink-metering rolls used in the printing industry to transfer an exact amount of ink to the printing cylinder. The importance of high quality anilox rolls has increased with the demand for higher quality printing. Improvements of the characteristics of anilox rolls have been achieved mainly by using laser-engraved, ceramic-coated rolls rather than the common chrome-plated and mechanically engraved rolls. The best results concerning the ceramic coating of anilox rolls were achieved by Cr2O3 coatings. These coatings require a bond coat for good corrosion resistance. By far the most-used technology to produce this bond coat is high velocity oxygen fuel (HVOF) spraying using NiCr material. In order to lower the cost of the anilox roll coating it has been investigated if NiCr can be replaced by the chromium steel 316L as bondcoat material. 316L was applied to the surface by HVOF. The characteristics of 316L / Cr2O3 layers were compared with respect to the required quality of the coating. The results were 316L / Cr2O3 coatings with good mechanical characteristics compared to NiCr / Cr2O3 layers. In particular, the metallographic sections showed compact coatings having a tensile adhesive strength slightly higher than and a corrosion resistance similar to the coatings with a NiCr bond coat.
