S1: A device X is typically made of iron.
S2: A device X is often made of iron. (A device X is usually made of iron.)
(Say, X is a hammerhead.)
Mister MicawberThe resultant percentage of iron hammerheads can be the same in all 3 of your sentences (typically, usually, often)-- but the expected percentage decreases in the order in which I have listed the 3 adverbs. Typically also suggests that it is standard practice-- a comment on consistency or regularity.Gotcha:)