Carbothermal reduction of ZrSiO4 for in situ formation of ZrO2-based composites using spark plasma sintering. Issue 2 (15th January 2023)

• Record Type: Journal Article
• Authors: Irankhah, Reza; Mobasherpour, Iman; Alizadeh, Masoud; Moosavi Nezhad, Seyyed Mohsen; Nikzad, Leila; Azar, Saeed Samadi
• Is Part Of: Ceramics international. Volume 49:Issue 2(2023)
• Page Start: 2681
• Page End: 2688
• Publication Date: 2023-01-15
• Subjects: ZrSiO4 -- Carbothermal -- Reactive spark plasma sintering -- ZrO2-Based composites; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2022.09.248
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: In the present study, ZrO2 based composites were synthesized in-situ and sintered by the novel RSPS-assisted carbothermal reduction of ZrSiO4 (Z) in the presence of graphite (G) and Activated Carbon (AC). The RSPS process was performed using a vacuum furnace at different temperatures of 1400–1600°C for 5–15 min under an external pressure of 30 MPa. The thermodynamic analysis was conducted on the synthesis process by FactSage software. The microstructure development and mechanical properties of RSPS-ed ZrO2 -based composites were investigated. The Phase evolution and phase content, as functions of temperature, were characterized using x-ray diffraction and FESEM/EDS analysis. The XRD studies showed that all primary ZrSiO4 was decomposed into ZrO2, ZrC, SiC, and SiO2 phases. The unreacted graphite or activated carbon was also identified in the samples. Finally, the hardness and flexural strength of the composites were examined by Vickers hardness and 3-point bending strength tests. The results indicate that the SPS-ed ZrSiO4 + Activated Carbon composite (ZAS-3) has the best mechanical properties. A density of 2.87 ± 0.05 g/Cm 3, an open porosity of 0.02%, a bending strength of 132.4 ± 11.2 MPa and a hardness of 9.86 ± 1.1 GPa were estimated for the SPS-ed ZrSiO4 + Activated Carbon mixture of powders at 1600°C.