Author:

Keywords:

Nanocomposites, Mechanical properties, Strength, ZrO2-WC, Science & Technology, Technology, Materials Science, Ceramics, Materials Science, nanocomposites, mechanical properties, strength, PARTICULATE COMPOSITES, MECHANICAL-PROPERTIES, TZP MATRIX, CERAMICS, TOUGHNESS, 0912 Materials Engineering, Materials, 4016 Materials engineering

Abstract:

Fully dense ZrO2-based nanocomposites with 5–40 vol.% WC were produced by hot pressing at 1450 ◦C for 1 h. The hardness and bending strength of the composites increases with increasing WC content, whereas the toughness hardly changes. An exceptionally high strength of 2 GPa combined with a hardness of 14.80 GPa and an excellent fracture toughness of 9.4 MPa m1/2 was obtained for the 2 mol% Y2O3 stabilised ZrO2- based composite with 40 vol.% WC. Such an attractive combination of properties is quite unique for a ceramic composite and is only matched by WC–Co cermets. The composites are substantially harder and stronger than the fine-grained Y-TZP, whereas the excellent toughness of Y-TZP is maintained. The strength improvement was accompanied with a change in fracture mode of the ZrO2 grains from intergranular to transgranular. The ZrO2–WC nanocomposites were found to slightly plastically deform before fracturing during bending.