That would definitely depend on the type of material you are looking at. For example, aluminium is a solid and a Lewis-acid. But an unoxidized block of aluminium could possibly just react with it's surface-atoms and nothing would really happen. This is since the bulk of your material would not get in contact to react, and only miniscule amounts of atoms make up the surface of macroscopic bodies. If your surface-layer atoms would, however, dissolve or liquify, meaning your solid acid would break up or the resulting product would not block the surface, your acid could react completely and eat through something. If you were taking frozen glacial acidic acid and a block of sodium hydroxide for example, you'd form water during reaction, which can dissolve the acid, base and product. Also they'd attract water from the air. So your acid would be used up completely and would go through the sodium hydroxide with time.