AISI 317L Stainless Steel Foil

AISI 317L Stainless Steel Foil (UNS S31703) is a molybdenum-alloyed low-carbon austenitic stainless steel foil offering measurably improved resistance to pitting, crevice corrosion, and uniform corrosion compared with 316L. Its molybdenum content of 3.0–4.0 wt% delivers a pitting resistance equivalent of approximately 28 versus 24 for 316L, extending reliable service into chloride-bearing and acidic environments where 316L reaches its limits. The low carbon ceiling of ≤0.030 wt% prevents chromium carbide precipitation during welding, eliminating post-weld annealing requirements in most applications. Room-temperature yield strength of 220–240 MPa and elongation of ≥35% support good cold formability by bending, roll forming, drawing, and hydroforming. Weldable by GTAW/TIG, GMAW/MIG, and SMAW processes using matching 317L filler. Typical applications include heat exchangers in dilute acid service, reaction vessels, chemical process piping, flue gas desulphurisation components, and pulp and paper equipment. In research, it provides a reproducible corrosion-resistant substrate for electrochemical studies and pitting resistance evaluation in chloride and mixed-acid environments.