Investigations on corrosion and wear behaviour of duplex stainless steel coatings reinforced with hardening components

This paper is dealing with corrosion and wear resistance results of protect ive duplex stainless steel coatings (X2CrNiMoN25-10-4) made by two-powder-p lasma weld surfacing with additional hardening components Cr2C3 and WC-WC2. First the developing of a process technique was important which allows an exact addition of hardening components and an as low as possible dissolutio n of carbides. The microstructure did not show the typical ferritic-austeni tic structure. The wear and corrosion resistance in sulphuric acid is very good and reveals the high quality of the protective coatings. However the c orrosion resistance in synthetic sea water is considerable reduced. Low gra in size and pre-heat temperatures of 100 degrees C have a positive influenc e on the corrosion resistance.