Monolithic ceramic body with mixed-oxide marginal region and metallic surface, method for producing same and use of same

A monolithic ceramic body with a mixed-oxide marginal region and a metallic surface;

• wherein the ceramic body has a core of an oxide of a first metal (I) and a marginal zone, the marginal zone comprising a mixed-oxide marginal region, which comprises the oxide of the first metal (I) and an oxide of another metal (II), which has a high affinity for oxygen, and a metallic surface of metal (II) on the mixed-oxide marginal region;
• wherein the marginal zone has been formed by altering the chemical composition of a marginal region of an unfinished ceramic body by means of an activation of the marginal region and a subsequent thermochemical treatment each under a negative pressure that is 10−3 mbar or less, and wherein the altering of the chemical composition distinguishes in that it results not only in an incorporation of ions of the metal (II) into the lattice of the ceramic material of the ceramic body;
• wherein the thermochemical treatment has been induced by ion implantation;
• wherein the mixed-oxide marginal region
• has a continuous concentration gradient of the first metal (I), starting from 100% in the core to 0% in the transition region to the metallic surface of the ceramic body, relative to the total metal content (I+II);
• and
• has a continuous concentration gradient of the other metal (II), starting from 0% in the core to 100% in the transition region to the metallic surface of the ceramic body, relative to the total metal content (I+II);
• wherein the oxygen concentration of the mixed-oxide marginal region remains constant;
• and
• wherein the monolithic structure of the ceramic body is formed without phase boundaries.