Ca-ATZ/Ca-ATZ+SiO ₂ functionally graded ceramic

The paper studies the structural features, phase composition and complex mechanical properties of two-layer composite ceramics based on alumina-toughened zirconia with silica added (Ca-ATZ/Ca-ATZ+SiO2). The ceramics under study were manufactured using a cost-effective technology involving grinding and mixing powders, layering of powder mixtures (different compositions), uniaxial pressing and two-stage sintering. It was found that at the interface of the compositions, there is an abrupt increase in fracture toughness (by 33%) and a decrease in hardness and Young’s modulus (by 8% and 7%, respectively). The possibility of manufacturing composite ceramics Ca-ATZ+SiO2 (with a thin surface layer, not containing SiO2) with a high ratio of hardness (not lower than 14 GPa) and fracture toughness (not lower than 12 MPa m1/2) was shown. Given the increased resistance to low-temperature degradation of the developed ceramics, this will increase the service life of products operated under high mechanical loads in a humid atmosphere.