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

摘要

Monolithic ceramic bodies that have a mixed-oxide marginal region and a metallic surface, where the ceramic body includes an oxide of a first metal (I), while the mixed-oxide marginal region includes the oxide of the first metal (I) and the oxide of a further metal (II) having a high affinity for oxygen, and the metallic surface includes the further metal (II). The mixed oxide marginal region includes a continuous concentration gradient of the first metal (I), from 100% in the core to 0% in the transitional region to the metallic surface of the ceramic body, and a continuous concentration gradient of the further metal (II), starting from 0% in the core to 100% in the transitional region to the metallic surface of the ceramic body, where the oxygen concentration in the mixed-oxide marginal region remains constant, and the monolithic structure of the ceramic body has no phase boundaries.

主权项

1. 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 an 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 by shifting the atoms of the marginal region to an energetically excited state 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 results in an incorporation of ions of the metal (II) into the lattice of the ceramic material of the ceramic body and also results in a reaction between oxygen atoms of the oxide of the first metal (I) and ions of the other metal (II); 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); andhas 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.