METHOD OF MANUFACTURE OF MAGNETITE ANODES FOR CATHODE CORROSION PROTECTION SYSTEM Russian patent published in 2002 - IPC

FIELD: powder metallurgy; electrochemical protection of internal surfaces of articles brought in contact with conducting aggressive media against corrosion. SUBSTANCE: proposed method consists in preparation of change which consists on natural magnetite is ground in ball mill to fractions of 1 to 5 mkm; used as binder is 3-% solution of polyvinyl alcohol; molding of charge is performed at pressure of 100 to 150 MPa at delay of no less than 1 min till blanks at ratio of their diameter to thickness ranges from 2.5 to 3.0; then blanks are subjected to degassing in vacuum cabinets at temperature of 300 C and pressure not below 10^-3 to -10^-2 mm Hg; sintering is conducted in vacuum furnaces at pressure of 10^-4 and temperature of 1300 to 1350 C for 6 to 10 hours followed by cooling to room temperature. EFFECT: improved quality of compact magnetite anodes at density close to density of natural magnetite; enhanced electrochemical and physical properties; increased rate of anodic dissolution and anode polarizability. 1 tbl