The mere presence of chromium carbides and
nitrides in ferritic stainless steels does not ensure
that they will be subject to intergranular corrosion.
On the contrary, the usual annealing treatment
for conventional ferritic stainless steels is
one that precipitates the carbides and nitrides
at temperatures (700 to 925 C, or 1300 to
1700 F) at which the chromium can diffuse back
into the depleted zones. These same treatments
would, of course, sensitize austenitic stainless
steels because of the much slower rate of diffusion
of chromium in austenite.