Effect of sintering pressure on microstructure and properties of hot pressed calcium-doped lanthanum chromate ceramic

doi:10.13251/j.issn.0254-6051.2022.11.012

Abstract

Abstract: High density calcium-doped lanthanum chromate ceramic (La_0.8Ca_0.2Cr_0.98O₃) was prepared by hot pressing under different sintering pressures. The effect of sintering pressure on microstructure, mechanical properties and electrical conductivity of La_0.8Ca_0.2Cr_0.98O₃ ceramic was studied. The results show that when the sintering pressure is greater than 58 MPa, the second phase CaCr₂O₄ can be detected in the sintered ceramics. There are two completely different forms of CaCr₂O₄ in the sintered ceramics. The increase of sintering pressure can not only improve the density of lanthanum chromate ceramic, but also inhibit the grain growth significantly. With the increase of sintering pressure, the flexural strength and hardness increase gradually, but the fracture toughness and conductivity decrease.

Key words: hot pressing sintering, La_0.8Ca_0.2Cr_0.98O₃ ceramic, high density, mechanical properties, conductivity

CLC Number:

TG132.2⁺4

Lai Xuping, Yan Weiwen, Wang Lianghui. Effect of sintering pressure on microstructure and properties of hot pressed calcium-doped lanthanum chromate ceramic[J]. Heat Treatment of Metals, 2022, 47(11): 76-81.

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