Hi, in the Encyclopedia under armor type theres rolled and I guess this is meant to be Rolled Homogenous Armor, RHA. But theres also concrete-enforced. Is this meant to be FHA, face hardened armor?

Don't know, but that sounds like that wonky german armor for magnetic mines?

You mean Zimmerit. But thats not an armor type. Its more like an coating on top of the armor. Its a paste. Zimmerit wasnt used in e.g. 1942.
It was used from 12/43 - 09/44.

Yes


No, "face-hardned" has two types, all are face hardened but with different technologies.

Concrete-enforced - is "German style" armor, saturation of the surface layer of carbon and alloying elements - nickel, manganese, molybdenum and etc.
Rolled, face-hardened - thermal treatment of the surface by a particular algorithm.

Result is the same, but different technologies used.

Hi Andrey, now I understand. Thx for your reply.