How common lorica segmentata actually was?

[Gaius Colletti]

It can also turn you carbon steel (which is a redundancy since all steel has a carbon content 0,7%-2%) into cast iron, one of the reasons metal was pretty much crap in the middle ages.

Your figures are wrong, Mild Steel alone can have up to .25% carbon, and can have significantly less as well, with high carbon having as much as 1.5% carbon content. Who said steel was crap in the Middle Ages? Some of the best metal working was done at this time? Ever see a gothic knight or some equipment used to make build cathedrals?

Are you saying Middle Age metal was less durable or less strong? Different types of steel have different properties, depends on what you intend to use it for

[Cerco 21]

I'm saying that before Bessamer steel manufacturing was at best an art, know by few.

I'm also saying that yes steel was far less durable and far less strong in the middle ages since you couldn't reach the temperatures needed for some phases (in the context of metalic crystalization), nor you had the proper knowledge and techniques of quenching and heat treatment. You obviously had rudimentary empiric knowledge, but again yes, most "steel" from the middle ages was closer to cast iron than steel.

Also remember that most things that reach us are likelly the best examples of work of the day.

You could actually "cheat" and make some good metal (from burying sheets and then fusing them, to the japanese process of folding softer and harder steel), but not in a consistent fashion.

My curiousity is if indeed the Romans could produce steel in quality AND quantity.

[Dan Howard]

You could actually "cheat" and make some good metal (from burying sheets and then fusing them.

Do you have more detail about this? What exactly is involved?

[Cerco 21]

You could actually "cheat" and make some good metal (from burying sheets and then fusing them.

Do you have more detail about this? What exactly is involved?

Yes. In the Iberian Peninsula (I live in Portugal - it could be done elsewhere as well) some smiths would forge sheets of metal, and then would ask the blessings of the earth gods by buring those sheets in the ground for around 2 years, since the first process would leave the "softer" crystaline structure on the outside of the sheet, when you recovered what was left of the rusting process you'd recover the "harder" metal structure, by forge joining these leftover metal sheets (maybe even ingots) you'd get a harder metal that you could then work into a weapon, usually a weapon since it was long and very very specific process.

[Dan Howard]

I've been trying for years to come up with a reasonable explanation for the passage in Diodorus whre he wrote that the Gauls,

bury plates of iron in the ground and leave them there until in the course of time the rust has eaten out what is weak in the iron and what is left is only the most unyielding...[V.33.4]

This passage is starting to make sense.

[Cerco 21]

I've been trying for years to come up with a reasonable explanation for the passage in Diodorus whre he wrote that the Gauls,

bury plates of iron in the ground and leave them there until in the course of time the rust has eaten out what is weak in the iron and what is left is only the most unyielding...[V.33.4]

This passage is starting to make sense.

Interesting, so other areas did the same, do you have any idea of the time frame in Diodorus account? The little we have in the museum seems to indicate that this practice was done as far back as 150BC.

Also does Diodorus mentions the reforging after the rusting process?

In the light of what we know today I can more or less infer what happend.(mind you this is mere conjecture based on what I'd do)

1. Smelting would leave a more or less isotropic crystaline structure
2. Forging this into sheets by beating the metal would "compress" the crystaline structure making it "harder" on the inside layers
3. Rusting it would remove the "softer" layers
4. "Welding" it at the forge would maintan the compressed structure achived by the first forge process and would relieve the accumulated stress.

Thus the metal would be stronger and would retain a degree of plasticity, and not become brittle as is the case you cold work steel without re-heating.