Abstract
Intercrystalline corrosion in chromium-nickel steels is considered from both a theoretical and practical standpoint. Laboratory tests were conducted to determine the effect on Invar alloy and 18 chromium-9 nickel alloy of boiling sulfuric acid containing copper sulfate. Specimens subjected to various heat treatment were tested. Polarization curves and passivation potentials of alloys are given.
The use of a potentiostat proved helpful in determining intercrystalline corrosion susceptibility, especially for steels with a low carbon content and those containing stabilizing elements which demonstrate only a slight tendency to intercrystalline corrosion. The extent of intergranular corrosion depends on the amount of precipitated chromium carbide and on the redox potential of the solution. 3.2.2