ΔE 19.8, loose: different enough that you should pick on purpose. Galvanized Steel is noticeably lighter, more saturated than Ironbreaker.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 20). Galvanized Steel is noticeably lighter, more saturated than Ironbreaker.
The same difference applies the other way round: Ironbreaker is noticeably darker, more muted.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Ironbreaker on the colour wheel See Galvanized Steel on the colour wheel
All matches: Ironbreaker equivalents · Galvanized Steel equivalents