Pressureless Densification of Zirconium Diboride with Boron Carbide Additions
The synergistic roles of boron carbide and carbon additions in the enhanced densification of zirconium diboride (ZrB2) by pressureless sintering have been studied. ZrB2 was sintered to >99% relative density at 1900°C. The combination of 2 wt% boron carbide and 1 wt% carbon promoted densification by removing surface oxide impurities (ZrO2 and B2O3) and inhibiting grain growth. Four-point bending strength (473±43 MPa), Vickers' microhardness (19.6±0.4 GPa), fracture toughness (3.5±0.6 MPa·m1/2), and Young's modulus (507 GPa) were measured. Thermal gravimetry showed that the combination of additives did not have an adverse effect on the oxidation behavior.
S. Zhu et al., "Pressureless Densification of Zirconium Diboride with Boron Carbide Additions," Journal of the American Ceramic Society, Blackwell Publishing, Jan 2006.
The definitive version is available at http://dx.doi.org/10.1111/j.1551-2916.2007.01936.x
Materials Science and Engineering
Keywords and Phrases
Boron Carbide Additions; Pressureless Densification; Zirconium Diboride
Article - Journal
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