In:
International Journal of Applied Ceramic Technology, Wiley, Vol. 21, No. 4 ( 2024-07), p. 2645-2650
Abstract:
This work investigated the effect of ZrB 2 content on phase composition, relative density, microstructure, and mechanical performance of Si 3 N 4 ceramics prepared by Si nitridation and hot‐pressing method. Si 3 N 4 ceramics were fabricated using Si powder by nitridation and hot‐pressing process. Results showed that the addition of ZrB 2 enhanced the transformation of α‐Si 3 N 4 into β‐Si 3 N 4 phase during nitridation, resulting in a greater fraction of β‐Si 3 N 4 (above 90 wt.%) phase in Si 3 N 4 ceramics with ZrB 2 after hot‐pressing. In contrast, ceramics without ZrB 2 had a lower ratio of β‐Si 3 N 4 (40.4 wt.%). The use of 2.5 vol.% ZrB 2 yielded a significant bimodal microstructure and increased fracture toughness to 5.0 ± 0.2 MPa·m 1/2 , but decreased Vickers hardness to 16.4 ± 0.5 GPa. However, increasing the ZrB 2 content to 5 vol.% and 10 vol.% led to a massive formation of equiaxed coarse β‐Si 3 N 4 grains and a significant decrease in Vickers hardness and fracture toughness.
Type of Medium:
Online Resource
ISSN:
1546-542X
,
1744-7402
Language:
English
Publisher:
Wiley
Publication Date:
2024
detail.hit.zdb_id:
2167226-X