PRESS ROLL WITH CERAMIC COATING, A METHOD FOR MANUFACTURING THE SAME AND COATING COMPOSITION

摘要

A press roll for a paper or board machine, a method for manufacturing a roll for a paper or board machine and a coating composition for a roll which enable the roll to endure difficult corrosion conditions. An adhesion/corrosion-protection layer having a thickness of from about 150.mu.m to about 300.mu.m is applied onto the frame part of the roll by a high-velocity flame spraying technique. The adhesion/corrosion-protection layer contains a nicke l- chromium alloy. A tight-ceramic layer having a thickness from about 50 .mu.m to about 150 .mu. m is applied onto the adhesion/corrosion-protection layer by a high-velocity flame spraying technique and includes from about 50% to about 100% of Al2O3 and optionally includes up to about 50% of TiO2 and/or any amount of Al2TiO5. A porous ceramic layer is applied onto the tight ceramic layer. The tight- ceramic layer may include only Al2TiO5 instead of Al2O3, with or without TiO 2.