Microstructures and Mechanical Properties of Titanium Silicon Carbon/Alumina and Titanium Silicon Carbon-Titanium Carbide/Alumina Composite Ceramics by Modifying Alumina Content Via In-situ Synthesized

Yulin Wei

Jun Ji

Hailing Yang

Sique Chen

Yingying Che

Deli Ma

Zhenyu Zhang

Baocai Pan

Guopu ShiEmail

School of Material Science and Engineering, University of Jinan, Jinan 250022, China

Abstract

Ti3SiC2/Al2Oand Ti3SiC2-TiC/Al2O3 composite ceramics with various Al2O3 fractions were prepared by Ti, Si, Al, TiC and Al2O3 powers via in-situ reaction. Al2O3 contents in raw materials could influence the reaction process of Ti3SiC2 generated. It would lead to reacting completely when the Al2O3 contents is in the range of 50 to 70 vol%, otherwise, TiC as an impurity would be found. Finally, the Ti3SiC2/Al2O3 composites with 54.4 wt% Ti3SiC2, and Ti3SiC2-TiC/Al2O3 composites with 54.7 wt% Ti3SiC2 and 9.2 wt% TiC were fabricated successfully. There were two types of TiC that existed in composites, called intragranular and intergranular particles. The Ti3SiC2-TiC/Al2O3 composite ceramics with 9.2 wt% TiC showed higher mechanical properties than the Ti3SiC2/Al2O3 composite. From the analysis of microcrack propagation paths, the dispersed TiC particles as reinforcement agents would cause significant crack deflection, improving the flexural strength and fracture toughness up to 492 MPa and 7.8 MPa.m1/2 respectively.

Microstructures and Mechanical Properties of Titanium Silicon Carbon/Alumina and Titanium Silicon Carbon-Titanium Carbide/Alumina Composite Ceramics by Modifying Alumina Content Via In-situ Synthesized