Chervins'ka N. Electrochemical characteristics of arc sprayed coatings and improvement of their corrosion resistance.

Object of study - electrochemical and corrosive processes on steels, aluminum and magnesium alloys with thermal sprayed coatings. Purpose - investigation of the electrochemical behavior of the thermally sprayed coatings of the basic Fe-Cr-B system, as well as the laser modified surface layers on steels, aluminum and magnesium alloys with the aim of their optimization concerning the parameters of their corrosion resistance. An electrochemical behavior of the electric arc coatings of the Fe-Cr-B-Al system, prepared by spaying with aluminum wires as well as powder cored wires in steel and aluminum shells on steels, aluminum and magnesium alloys has been investigated. An influence of both laser remelting of thermally sprayed coatings and laser modification of the surfaces of aluminum and magnesium alloys with the SiC disperse particles on their corrosion characteristics has been investigated. It was established that for the purpose of improvement of the corrosion and wear resistance of high strength aluminum alloys, a preheating of the alloys up to 170….270 C during their surface laser reinforcement with SiC disperse particles is useful. This results in the increasing of the modified layer depth up to 3 mm with the homogeneously distributed particles of silicon and aluminum carbides. For essential improvement of wear and corrosion resistance of metal parts it is useful to apply a plasma electrolytic treatment of arc sprayed coatings on the basis of aluminum, deposited on steel, aluminum and magnesium alloys, which enhances their corrosion resistance 10-15 times.