Download file (741 KB)
Download as zip (738 KB)

Collection

Citation

Description:

This Journal "Poroshkovaya Metallurgiya" ISSN 0032-4795 publishes papers in Ukrainian, and Springer Nature immediately translates them into English as "Powder Metallurgy and Metal Ceramics" (https://link.springer.com/journal/11106). This paper, "Mechanical and Dielectric Properties of Si3N4-Based Ceramics." Powder Metallurgy and Metal Ceramics, Vol. 63, Nos. 5-6, Sept., 2024 (Ukrainian Original Poroshkovaya Metallurgiya https://www.researchgate.net/journal/Poroshkovaya-Metallurgiya-0032-4795> Vol. 63, Nos. 5-6, May-June, 2024)

The effect of sintering-activating Y2O3 and SiO2–Y2O3 additives on the mechanical and dielectric properties of Si3N4 and Si3N4–BN ceramics consolidated by spark plasma sintering was examined. The heating rate and applied pressure were maintained at 50°C/min and 35 MPa, respectively. The holding time at a sintering temperature of 1800°C varied depending on the composition of the oxide additives. The Si3N4–BN ceramics with Y2O3–SiO2 additives exhibited a 30% reduction in mechanical properties (hardness and fracture toughness) compared to Si3N4–Y2O3 or Si3N4–Y2O3–SiO2 ceramics. The Si3N4 ceramics demonstrated resistance to deformation at temperatures ranging from 20 to 900°C. Specifically, Si3N4 ceramics with Y2O3 or Y2O3–SiO2 additives showed average strengths of approximately 950 and 820 MPa, whereas Si3N4–BN ceramics demonstrated a strength of 490 MPa. An increase in temperature from 1000 to 1400°C for all ceramics studied resulted in a gradual decrease in bending strength to approximately 200 MPa. The strength at room and elevated temperatures, Vickers hardness of approximately 4 GPa and 15.5 GPa, and fracture toughness of about 7.7 MPa · m1/2 meet the current requirements for this type of ceramics. Radiofrequency measurements showed that dense Si3N4-based ceramics had a dielectric constant of 8. When 10 wt.% BN was added, the dielectric constant of the composite decreased by approximately 8%. Additionally, residual porosity of about 10% further decreased the dielectric constant of the Si3N4–BN composite by around 13% (ε ~ 6.3). This reduction in the dielectric constant had a positive effect on radio transparency. The dielectric loss tangent of the test ceramics did not exceed 2 · 10–3.

Rights:

• In Copyright
  

  This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Nature’s AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: https://doi.org/10.1007/s11106-025-00464-6

Keyword: Silicon nitride, mechanical properties, hardness, fracture toughness, Dielectric properties, SPS

Date published: 2025-04-01

Publisher: Springer Nature

Journal:

• Powder Metallurgy and Metal Ceramics (ISSN: 10681302) vol. 63 p. 308-317

Funding:

• NIMS AB3080 (Only part of O. Vasylkiv was funded with the Group budget AB3080 NIMS. The study in total was endorsed by the NAS of Ukraine)

Manuscript type: Author's version (Accepted manuscript)

MDR DOI: https://doi.org/10.48505/nims.5459

First published URL: https://doi.org/10.1007/s11106-025-00464-6

Related item:

Other identifier(s):

Contact agent:

Updated at: 2025-05-02 10:26:05 +0900

Published on MDR: 2026-04-01 08:23:53 +0900