In:
Key Engineering Materials, Trans Tech Publications, Ltd., Vol. 512-515 ( 2012-6), p. 723-728
Abstract:
The sinterability of ZrB 2 -20vol.% SiC ceramics by high-energy ball milling as well as introduction of Zr and Al as sintering additives. Densification process and microstructure of ZrB 2 -SiC ceramics were investigated. After high-energy ball milling, the average particle size decreased to about 500 nm-2 μm, and ZrB 2 -SiC powder can be sintered to 98.92% theoretical density at 1800 °C, but a trace of amount of oxidation (ZrO 2 ) were detected in sintered sample. Introduction of Zr, Al and C combined with high-energy ball milling enhanced the densification of ZrB 2 -SiC ceramics and reduced the particle sizes, and the relative density of obtained ceramic reached up to 99.49% at 1800 °C. The additions of Zr, Al and C can remove the oxide impurities of the surface of ZrB 2 particles and form a reaction between oxide impurities. The fracture toughness increased of the 40% when ZrB 2 powders were milled by high-energy ball milling, and increased to 4.77±0.18 MPa•m 1/2 . However, the attrition-milled composites had lower hardness and Young’s modulus, which was attributed to the presence of a second phase in the grain boundaries.
Type of Medium:
Online Resource
ISSN:
1662-9795
DOI:
10.4028/www.scientific.net/KEM.512-515
DOI:
10.4028/www.scientific.net/KEM.512-515.723
Language:
Unknown
Publisher:
Trans Tech Publications, Ltd.
Publication Date:
2012
detail.hit.zdb_id:
2073306-9
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