I disassembled a 1a before and I do not recall seeing any disc. May be that is why my focusing knob has free play in it. It still focuses fine but just annoying. If you find out what the materials are, can you please post them here. Thanks...
Today dis-assembled an Ikoflex 1a of a later production date then the first one. It suffered from lousy focusing. In this one the Pressure Disc is clearly made from metal. The Friction Discs also seem to be made of another material then in my first Ikoflex. Could be that they are made from some kind of carbon.