Yes. Curiasses, hauberks, chestplates... They are all acceptable. But plated armour is not

Iron and steel were available, but Steel is hyper-rare and expensive, and iron isn't as hard. Bronze is good for armour for its strength, but you need tin and copper to forge it. That means either having ores or importing them. It's also rotten as a weapon metal, as it dulls quite quickly.
 Iron is far more common, and is good for blades, as it keeps its edge for longer, but weaker as an armour.
Steel is far rarer, and is only really usable for nobles or important figures - even a rich nation would only ever forge about ten. It can also be used in sword edges, which takes up much less of the metal. I'd personally disallow any standard military unit wearing steel armour, but a few steel weapons are acceptable.