Thermal spraying of a high nitrogen duplex austenitic-ferritic steel

High nitrogen steels have received more and more attention due to their hig h comprehensive properties in recent years. Thermal spraying of such steels provides alternative coatings with improved mechanical and corrosion perfo rmance compared to some of today's conventional steel coatings. In this stu dy a high nitrogen duplex austenitic-ferritic steel was sprayed using diffe rent thermal spray processes. The influence of the process and spray parame ters was investigated. An increase of the nitrogen content could be realize d by plasma spraying using nitrogen as a secondary plasma gas. However, the increase of nitrogen took place non-uniformly. The HVOF coatings provided better wear and corrosion properties than the plasma spray coatings. (C) 20 01 Elsevier Science B.V. All rights reserved.