Q: We are in search for a bolt material that can handle sulfuric acid – compatible with 96% H2SO4. The exposure should be low and only on an infrequent basis. Also, these applications when H2SO4, DI Water is used to flush and clean off the surfaces during any maintenance that occurs inside the platform.
A: Without knowing the temperature of your application it’s impossible to give a firm recommendation as the corrosiveness of the acids is highly dependent on the temperature. However, if you are below 140F Hastelloy C276 bolts would be a robust choice to consider. See the corrosion curve below (You want to be as far below the 5mpy line as possible.)