Abstract
A study has been made of ferritic stainless steels, which are not susceptible to stress corrosion cracking and comparable in corrosion resistance to type 304 steel in relatively mild environments. Cold rolled sheets of various compositions are prepared in the laboratory from ingots made by vacuum induction melting and their resistance to pitting, general corrosion, and stress corrosion cracking are examined. Good corrosion resistance is obtained by 19% Cr, 2% Mo, and Ti and/or Nb equivalent to more than 16 times of the C+N content and maintaining the interstital elements, i. e., C and N as low as possible.
While Ti improves the ductility of the weld, the element causes the surface defects such as Ti-streak on cold rolled strip, when a sufficient amount of Ti for stabilization is added. Therefore, combined additions of Ti and Nb are preferable.
