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Sintering boron carbide ceramics without grain growth by plastic deformation as the dominant densification mechanism.

ABSTRACT: A new ceramic sintering approach employing plastic deformation as the dominant mechanism is proposed, at low temperature close to the onset point of grain growth and under high pressure. Based on this route, fully dense boron carbide without grain growth can be prepared at 1,675-1,700 °C and under pressure of (≥) 80 MPa in 5 minutes. The dense boron carbide shows excellent mechanical properties, including Vickers hardness of 37.8 GPa, flexural strength of 445.3 MPa and fracture toughness of 4.7 MPa•m(0.5). Such a process should also facilitate the cost-effective preparation of other advanced ceramics for practical applications.

SUBMITTER: Ji W

PROVIDER: S-EPMC4622079 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Sintering boron carbide ceramics without grain growth by plastic deformation as the dominant densification mechanism.

Ji Wei W Rehman Sahibzada Shakir SS Wang Weimin W Wang Hao H Wang Yucheng Y Zhang Jinyong J Zhang Fan F Fu Zhengyi Z

Scientific reports 20151027

A new ceramic sintering approach employing plastic deformation as the dominant mechanism is proposed, at low temperature close to the onset point of grain growth and under high pressure. Based on this route, fully dense boron carbide without grain growth can be prepared at 1,675-1,700 °C and under pressure of (≥) 80 MPa in 5 minutes. The dense boron carbide shows excellent mechanical properties, including Vickers hardness of 37.8 GPa, flexural strength of 445.3 MPa and fracture toughness of 4.7 ...[more]

PMID: 26503706

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