Official Answer
Answer
316 Stainless Steel (ASTM A313) is selected for its molybdenum content, which provides superior resistance to pitting and crevice corrosion in chloride environments. However, 316 SS has a lower tensile strength ($S_{ut} \approx 1100$ MPa in spring temper) and lower modulus ($E \approx 193$ GPa) than 17-7PH. This means for the same load, a 316 SS spring must be thicker or have more waves. It is non-magnetic in the annealed state but becomes slightly magnetic when cold-worked. For high-pressure chemical seals, it is often the only viable choice despite the performance trade-offs compared to 17-7PH.
