PURPOSE: To provide the title steel contg. Cr, Mo, C, N, Si, Mn, P, S, Nb and Ti each in a predetermined percentage other than the balance Fe and impurities and especially characterized by reduction of Mn and addition of a slight amount of Ti.
CONSTITUTION: This Nb stabilized ferritic stainless steel consists of, by wt., Cr 16W25%, Mo≤3%, C≤0.01%, N≤0.01%, Si≤0.5%, Mn≤0.2%, P≤0.03%, S≤0.01%, Nb 15×(C+N)%W0.4%, Ti 0.05W0.2%, Al≤0.1%, and the balance Fe and inevitable impurities. The amount of Mn added is reduced as low as possible to control formation of MnS which becomes an active site for local corrosion and to improve the local corrosion resistance of the Nb stabilized steel, and such a slight amount of Ti having high sulfide forming capacity is added. As a result, this steel can remarkably be improved in pitting corrosion resistance and crevice corrosion resistance as compared to conventional steel.
ADACHI TOSHIROU
KANEZASHI HISAYOSHI
| JPS5188413A | 1976-08-03 |
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