Comments on Specific Grades
18-10 (1.4301, 304) - limited use in dilute acids 5% maximum at room temperature. Increasing temperature quickly makes the steel useless. Acceptable above about 90% at room temperature.
17-12-2.5 (1.4401, 316) - This grade offers a significant advantage over 304 at low concentrations, up to 22% at room temperature only gradually falling with temperature up to 40 deg C and then more quickly to about 5% at 60 deg C.
Duplex Steels - 2304 (1.4362) is similar to 1.4401 (316) at room temperature but only gradually falls off with temperature, still allowing about 8% at 80 deg C. 1.4462 (2205) is acceptable to as high 40% at room temperature falling to about 12% at 80 deg C. Superduplex 2507 (1.4410) offers only limited improvement to 45% at room temperature.
904L (1.4539) - This steel was specifically developed for sulphuric acid use and van be used across the whole concentration range up to 35 deg C.