Lorica Hinge Durability

[marsvigilia]

While working you will reach the point were the metal looses it's plasticity and will break, crack etc. when you try to deform it. I don't know the correct term for this state. Translated literally from the dutch term it would be 'metal-tirednes'.

In English the term is "metal fatigue", which is essentially the same.

@marsvigilia: The romans used many different kinds of brass. It is incorrect to say that aurichalcum was more like what we know as red brass/tomback. For rivets brass that consisted out of Copper (Cu) with only a slight ammount of Zinc (Zn) was used. This is just because it's easier, as this metal is softer than yellow brass (=brass with a higher Zn content). But more decorative things such as florettes on helmets and loricae were made out of brass with a high Zn content, to have a nice golden colour. The name 'aurichalcum' consists out of aurum (gold) and chalcum (copper). And can be translated as 'golden copper'.

Actually, ‘red brass’ (C230 85%Cu 15%Zn), is hardly red at all. ‘Red brass’ is very close in appearance to ‘yellow brass’ (C260 70%Cu 30%Zn & C270 65% Cu 35%Zn) but actually looks closer to gold. It is still used in American Indian jewelry as a relatively inexpensive alternative to gold. In this, the name "golden copper" makes sense. But it does NOT look like copper. ‘Gilding brass’ (C210) has just 5% zinc, and ‘commercial bronze’ has 10% zinc, note "bronze" is a bit of a misnomer as it has no tin in it. It is my understanding that the Romans did generally use brass at about 5% zinc for rivets, but 'red brass' has 15% zinc and really is closer to orichalcum. This makes perfect sense as ‘red brass’ is closer in appearance to gold and easier to work than ‘yellow brass’. The only disadvantage ‘red brass' has, is that it is harder to find in the modern context.

M.C. Bishop, "Lorica Segmentata Vol I", p77\\n[quote]Orichalchum, which is almost golden in appearance was a binary alloy of copper (80%-85%) and zinc (20%-15%) and was widely used in military equipment from the 1st to the 3rd centuries AD. As such it closely resembles the modern alloys of “low brassâ€