Patent ID: 8485042

Claim:
A method for manufacturing an elastic deformation body made of an Al 2 O 3 ceramic by application of an alumina, comprising the steps of: forming a mixture including alumina, including MgO components: producing from the mixture a pressable spray granulate; and the spray granulate is then formed by means of a uniaxial pressing method to a homogenous green body, wherein: the alumina, including MgO components present in given cases, has a purity of at least 99.9%, and wherein MgO amounts to no more than 1000 ppm, with respect to the mass of the Al 2 O 3 ; the alumina, with respect to the mass of the Al 2 O 3 , has, in sum, an impurities content of less than 200 ppm, of SiO 2 , Na 2 O, K 2 O, CaO and other inorganic impurities; the alumina has a specific surface area of not less than 10 m 2 /g; the alumina has a grain size d 50 , at cumulative 50 mass %, of no more than 0.3 μm; with the alumina, as well as organic and, in given cases, inorganic additives, there is produced via aqueous processing a homogeneous mixture; the mixture, with respect to the mass of the Al 2 O 3 , contains up to 1000 ppm MgO; the mixture, with respect to the mass of the Al 2 O 3 , contains not less than 200 ppm MgO, the mixture, with respect to the mass of the Al 2 O 3 , has, in sum, an impurities content of less than 200 ppm, of SiO 2 , Na 2 O, K 2 O, CaO and other inorganic impurities; the green body is exposed to a one- or multi-stage sinter process, the resulting elastic deformation body has a bending fracture stress C c , whose distribution F(σ c ) is given by the Weibull parameters σ 0 ≧800 MPa, and m≧24; the average grain size of sintered material of the deformation body, which is ascertained as median value of the cross sectional distribution, amounts to no more than 2 μm, and the sintered material of the deformation body has a density of not less than 3.98 g/cm 3 .