Brass/bronze Vs. Steel/iron helmets

[arklore70]

Practical question here.

Brass/bronze is softer than steel/iron. What, if any, advantages are there over a brass/bronze helmet over a steel/iron helmet, beside personal preference and appearances?

Any historical note of legionaries using there helmets like the old U.S. Army steel pot helmet for shaving, hygiene, and cooking?

Cheers

Mike

[Matt Lukes]

Copper alloy doesn't corrode at the drop of a hat the way iron does- that's a real plus in the field.

As for using them as pots/ etc., well while I'm unaware of the details of the recent discovery of helmet padding material, the only other reference I've heard of spoke of it being glued in, so at least in those cases, cooking, etc. was definitely out. Given that Legionaries carried dedicated cooking vessels, water jugs, etc., it seems unlikely they'd use their helmets- especially since the helmet was probably a fairly valuable piece of equipment.

American soldiers' 'extra' uses of their M1 helmets is probably unique because of its 2 part nature- I'm not aware of any other helmet where the suspension system isn't attached to the steel directly, so others simply couldn't be used the same way- unless the helmets owner didn't mind a soaked liner...

Matt

[Dan Howard]

Properly cast and work-hardened copper alloys are superior to wrought iron and equal to all but the best hardened steels. The only real advantage iron has over bronze is that it is more readily available and hence cheaper. If copper and tin were as easy to find as iron then it is likely that we would never have had an "iron age" since there is no practical reason to make the switch to iron.

[Sassanid]

Properly cast and work-hardened copper alloys are superior to wrought iron and equal to all but the best hardened steels. The only real advantage iron has over bronze is that it is more readily available and hence cheaper. If copper and tin were as easy to find as iron then it is likely that we would never have had an "iron age" since there is no practical reason to make the switch to iron.

Hello Dan,

I am not saying you are wrong, and I am certainly no metallurgist - but that goes against everything I was taught or have learnt on the subject.

I have always been told iron is superior to copper alloy in nearly every respect, excepting the corrosion problem. I accept cast iron could be ropey, but so could cast copper alloys. It needs to be done properly.

Andrew

[DAN OF BRITANNIA]

Speaking to a chemist friend of mine (also a re-enactor) about this very subject he says that brass is an alloy of copper and zinc (as most of you know no doubt).

The Romans certainly knew about zinc but the processes for extracting zinc from its ore were apparently too difficult to have been cost effective on an industrial scale (he says that modern processes involve blast furnaces and large amounts of electric current).

Before zinc was exploted as a metal, compounds of it were certainly used for healing wounds and sore eyes.

The term brass occurs in the Old Testament, but there's little evidence that an alloy of zinc and copper was used in such early times. The translation - "brass" might equally well be another reference to bronze or variation on the alloy of copper, both of which were in common use.

Marco Polo (much later) had described the zinc oxide being used in Persia and referred to the Persians preparing something called tutia (zinc-vitriol solution) for treating sore eyes.

Strabo (66 B.C. - 24 A.D.) mentions the Cyprian ore containing 'the cadmian stones, copper vitriol, and tutty' - the constituents from which brass can certainly be manufactured.
There is specuation that 'brass' was produced in Augustus' reign combining calamine, charcoal and copper.

Adjusting the mixture of tin & copper (to make bronze) can yield a lighter coloured 'brass-like' alloy - making modern brass on re-enactment fixtures more justifiable, especially when one considers that bronze now seriously competes with silver in price terms.

He's threatening to write a paper on it one day (I must confess I am relating this second hand and am no chemist myself).

Hope that helps.

[Marcus Mummius]

What I have been told is the following: in the beginning of the Bronze Iron transition the early ironworking skills were quite bad and the end products weren't better or stronger than the bronze ones. The advantage was indeed that iron was readily available. We have to consider the folowing: how did the Bronze age people know that iron was readily available? They didn't use it so why would they know the places to find it??? So the transition is likely to be caused by a lack of Bronze, the inability to acquire enough of it. This could be caused by collapsing trade networks, social strife etc...

On the helmets: I too think the major advantage is that brass or bronze doesn't rust. Also these helmets can reused to make a new one. A iron helmet that cannot be repaired is useless and just had to be thrown away.

Kind regards,

[Felix]

I don't think there is any great mystery about finding iron ore. I have no doubt the Bronze Age men, in particular metal-workers, knew what iron ore looked like - even if they didn't know it contained iron or how to extract said iron. Merely the process of prospecting for copper, tin, etc. would have meant stumbling over a fair amount of iron ore. Once someone figured out a way to extract useful metal out of these ores, I have a feeling the conversation went like this:

"...you mean you can get good metal out of that stuff? Holy -----, there are huges piles of those rocks across the river and up in the hills!"

Bronze continued to be widely used into the Iron Age, and as far as I know there is no evidence of a breakdown in the supply of bronze. As noted above, early iron quality may have been inferior to bronze but it was available in large quantities.

[Marius_Ursus]

I was reading about the history of metallurgy and learned that back in the time of Sumer, and later Assyria, iron was considered a precious metal because it was hard to get at. I don't know if the author meant that it's hard to get iron out of ore or if it was difficult to locate the ore.

Iron has a higher tensile strength, so it's less likely to give when bashed. Evidently that's also the reason it holds an edge better. However, as others have stated, the lack of oxidation in bronze makes it desirable.

Steel offers more protection. Bronze offers longer life.

Someone should have plated bronze onto steel to develop the ultimate helmet, I suppose. :lol:

[Dan Howard]

Start with this book.
"The prehistory of metallurgy in the British Isles" by R.F. Tylecote:
He samples bronze and iron weapons and tools. It is quite clear that properly cast and work-hardened copper alloys (alloys that were known and used in the Bronze Age) are superior to wrought iron in both hardness and toughness). They are comparable to most of the steels that were available at the time. Only the best quench-hardened steels are superior to bronze. Iron did not replace bronze because it was superior in performance.

[mcbishop]

Someone should have plated bronze onto steel to develop the ultimate helmet, I suppose.

No, they'd have made a battery: all it needs is a little rain and some crud and Bob's your uncle - electrolytic corrosion in a trice. This is the problem suffered by lorica seg and one familiar to anyone who owns a LandRover (in the latter case it's a duralumin/steel mix, but the same principle applies). Of course it was actually done with brass-skinned ferrous cavalry helmets in the 1st century AD.

I have talked at some length with David Sim on the copper alloy/ferrous issue in terms of armour and helmets and he assures me that it is possible to make copper-alloy armour every bit as good as its ferrous equivalent - the trick lies in the working, not the composition.

Incidentally, Roman brass was made by a process known as cementation, the limits of the technology meaning that it was only possible to get a maximum 28% zinc component. There was a convenient source of calamine in the lower Rhineland.

Mike Bishop

[ambrosius]

[This is the problem suffered by lorica seg and one familiar to anyone who owns a LandRover (in the latter case it's a duralumin/steel mix, but the same principle applies). Of course it was actually done with brass-skinned ferrous cavalry helmets in the 1st century AD. Mike Bishop

If memory serves, Duralumin was used in the sixties for supersonic jets
(like the B-58 Hustler - Mach 2 SAC bomber) as it combined the lightness
of Aluminium with the the strength afforded by being an alloy. Something
like 94% Aluminium, 4% Copper and a couple percent Magnesium and
Manganese (or something like that :wink: ) I guess it would be the 4%
of Copper that causes the problem in the LandRovers, then. 8)

Ambrosius

[arklore70]

Gents,

this is extremely interesting.

any good web sites on this topic?

Here is a question, which do you prefer for your impression...brass/bronze or iron/steel.

I think brass/bronze looks very nice....but how does it hold up compared to iron/steel.

[Marius_Ursus]

Someone should have plated bronze onto steel to develop the ultimate helmet, I suppose.

No, they'd have made a battery: all it needs is a little rain and some crud and Bob's your uncle - electrolytic corrosion in a trice.

Mike Bishop

And you don't think that's funny? :twisted:

[A_Volpe]

Sorry I'm not getting the obvious, since I'm not a chemist or a metalurgist - What was happening to LandRovers? Were they crumbling because of the reaction of the composite metal?

The mention of the battery makes me think of a question a curious and enthusiastic 6 year old boy asked me at a program once - "Did the Knights have Electricity?" - and while trying very hard not to laugh, so as not to hurt his feelings, I said "No, they did not have electricity, but if they did I think it would have been VERY interesting"

but also, I'm reminded of a TV series here in the states called "Mythbusters" which is a terrific program if I might add - But one episode they were trying to figure out how the ancient (assyrian? babylonian?) clay pot "batteries" worked, and what they could have been used for.

One of the results/theories they discovered is that they could do Metal Electroplating...Which for such "ancient" technology to me sounds really cool and has all sorts of implications....Is there evidence of [Romans] using electroplating? Is it a possible technique they may have had to obtain certain properties in metals?
- rememeber I don't have much knowlegde in metal stuff, so go easy.
(sorry this is getting a little off topic)

[Robert Vermaat]

but also, I'm reminded of a TV series here in the states called "Mythbusters" which is a terrific program if I might add - But one episode they were trying to figure out how the ancient (assyrian? babylonian?) clay pot "batteries" worked, and what they could have been used for.
One of the results/theories they discovered is that they could do Metal Electroplating...Which for such "ancient" technology to me sounds really cool and has all sorts of implications....Is there evidence of [Romans] using electroplating? Is it a possible technique they may have had to obtain certain properties in metals?
- remember I don't have much knowlegde in metal stuff, so go easy.
(sorry this is getting a little off topic)

That's the 'Baghdad Battery', supposedly from the Parthian period. And yes, it's been tested before, after which the testers suggested that museums should have another look at their 'solid gold' ancient objects. hock: