The Effect of Boron and Carbon on the Structure and Corrosion-Electrochemical Behavior of Kh20N20 Austenitic Stainless Steel

摘要

Effects of boron microadditives (<0.001- 0.016%) on the structure and corrosion-electrochemical behavior of Kh20N20 steel with differing carbon content (0.002-0.094%) in acidic environments is studied with the use of track autoradiography, X-ray phase analysis, and light and electron microscopy, as well as electrochemical and chemical methods. Polarization measurements were carried out in 1 N HClO_4 + 40 g/L Cr(VI) solution. Particular attention is paid to the role of boron and carbon in the development of intergran-ular corrosion in the steels of different structure types (single-phase systems or structure with second phases) at potentials of the active-passive transition, the end of the passive range, and repassivation.