Effect of Heat Treatment on Corrosion Activity of Nonmetallic Inclusions and Steel Corrosion Resistance in Aqueous Media

Results of the studying the effect of heat treatment on the corrosion activity of non-metallic inclusions in contemporary steels, and correspondingly on corrosion resistance of the steels themselves, as applied to the conditions of oil-field pipeline operation, are presented. It is shown that after heat treatment (quenching and tempering) steel contamination with nonmetallic inclusions detected by Oberhoffer reagent and affecting steel corrosion resistance decreases (some nonmetallic inclusions lose their corrosive activity), which ensures an increase in corrosion resistance of steel (obtaining lower values saturation current density when tested by an electrochemical method for assessing corrosion resistance).