Cold working and bending during boiler manufacturing can induce strain hardening in austenitic stainless steel, potentially compromising creep ductility and leading to premature failures during operation. While design codes like ASME I, PG 19 provide guidelines for maximum strain levels before solution treating is required, industry concerns suggest these limits may be too high, prompting some boiler manufacturers to implement more conservative thresholds. This study examined the creep ductility of four austenitic stainless steels (TP310HCbN, XA704, TX304HB, and Sanicro 25) at prior strain levels of 12% and 15%, with Sanicro 25 demonstrating the highest ductility, followed by TX304HB, XA704, and TP310HCbN. Solution annealing successfully restored creep ductility to exceed 10% elongation in all materials, though this treatment may be necessary at strains of 12% and 15% for all materials except Sanicro 25 to ensure adequate creep ductility. The findings suggest that ASME I PG 19 guidelines for austenitic stainless steels containing Cb, V, and N should be reviewed, as lower strain limits could help reduce strain-induced precipitation hardening failures.

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