Thanks for your hints.
skogsgurra: very good page, but I didn't found some specific BH curves.
EdStainless: Probably exacly what I was looking for. I think it would be
ASM Handbook Volume 01: Properties and Selection: Irons, Steels, and High-Performance Alloys.
Unfurtunaty there are probably american and not europeen standards, but thats not really a problem. but kind of expensive... (and not in our libraries... have to search once again)
I'm looking for a material for a voice coil (hysteresis is no problem) with a high saturation that is more or less easy to mill. and it has to be a standard material (to avoid supplier problems in production).