Stabilization of austenitic stainless steel

Abstract

A stu dy was m a de of t he resistance to in tergra nui a r atta ck of 23 18 % Cr-10 % 1\i a ustenitic co rros ion-res istin g steels in 12 different init ial co ndi t io ns. Suscept ibility to intergranula r attack was determined a fter seven sensit izin g t rcat me nLs; foll owed b y exp os ure for a m ax imum of 1. 4 d ays in a boilin g a cidified copper s ulfate sol ut io n. It ,,·as fo und t hat max imum s usce pt ibility to in tergran ula r at tack was de velop ed by sensit iz ing e ither 8 o r 21 d a~' s at ' ,020° F. Th e straigh t carb on a uste n itic sLeels were quite v ulner able to attack , alt ho ug h dec rcase in ca rbon co n ten t dec reased the degree of v uln e r-ab ili ty. Th e eolum bium-a nd t ita ni u m-t reated steels we re sa t isfactor ily resis lan t to attac k provid ed the Cbl C or Ti l C rat ios we re s u.tri ciently hi g h. These !"atiOH va ri ed , dep e nding on the initial co ndi t ion of the steel. Th e carbon con te nt of the t reated steels h a d no influ e nce upon t he res istance to in te rg ra nu la r attack , t he p re do min ating fa cto r bein g lhe Cb /C or T il C r a Li o.