Simulation of densification of ceramic materials based on boron carbide during high-speed sintering under pressure

DOI: 10.62564/M4-VD1637

Anatoliy Maystrenko, Vasyl' Dutka, Vitaliy Kulich, Oleksandr Borymskyi

V. Bakul Institute for Superhard Materials, Ukraine


Strength characteristics of ceramic materials, obtained in a result of sintering under pressure, significantly depends on their density. The sintering regime parameters as well as grain growth affect the density of the sintered material. In order to achieve high density, it is necessary to minimize grain growth. Therefore, it is important to predict the evolution of the sample material density and grain growth at the final sintering stage. At the present time, a number of densification models of ceramic powders during sintering under pressure have been developed. For the application of these models, it is important to determine their parameters. One of the densification models is the Skorohod-Olevsky model. Since the densification process of powder samples by high-speed sintering under pressure (HSSP) is very fast, the creep of the crystal lattice and grain boundaries can be considered as the dominant densification mechanism. Hence, the densification model can be limited to only the component that describes the mechanism of generalized creep. Therefore, the number of model parameters that need to be identified for simulation of densification is reduced. The purpose of this work is to apply a linear regression approach to determine the parameters of Skorohod-Olevsky densification model of powder samples based on boron carbide during HSSP according to experimental data, and to model the powder materials compaction using these parameters. The parameters of material densification model were determined using the results of HSSP-experiments of powder samples with two compositions based on boron carbide. A computer model of the densification of viscous porous materials was developed, taking into account grain growth. Modeling of the densification of powder materials during HSSP-process was carried out. It is shown that at noticeable grain growth of the sample material during HSSP, in order to obtain a dense composition it is necessary to increase the holding time. It is also shown that in this case, one of the alternatives to increasing the exposure time is the increasing of the working pressure.

Keywords
boron carbide, high-speed sintering under pressure, densification, grain growth, modeling.

Acknowledgments
Not provided

References
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