Brake unit with a ceramic brake disk bolted to a hub

A brake unit has a ceramic brake disk and a metallic hub with a radially overlapping edge zone at which they are bolted together, the brake disk having reception bores or slots at its inner edge region for receiving the bolts. These bores or slots are lined with a sleeve of plastically deformable material or the disk material is intentionally made plastically deformable locally in this region. An Independent claim is also included for producing the above brake unit by subjecting a mixture of carbon fibres, fibre bundles or felt, binder and filler to moulding and setting, pyrolysing the resulting green body, infiltrating the resulting porous body with molten silicon and ceramicising. Production of an only partially ceramicised brake unit is achieved by (a) doping the green body or the porous body with boron and/or a boron compound in the regions not to be ceramicised; (b) producing these regions as separate green bodies from a starting material containing boron and/or a boron compound as filler and assembling to a brake disk before pyrolysis; or (c) producing these regions as separate pyrolysed porous bodies which are doped with boron and/or a boron compound prior to assembly for ceramicising. Further Independent claims are included for a brake unit and its production, in which the brake disk consists of fibre-reinforced ceramic material bonded to a hub of the same fibre matrix, the hub containing boron and/or a boron compound and its fibre matrix merging into that of the brake disk via a transition region of silicon carbide.