|About this Abstract
||Materials Science & Technology 2011
||MS&T'11 Poster Session
||237 Mechanical Properties and Oxidation Behavior of Spark Plasma Sintered ZrB2-ZrC-SiC Composites
||Ipek Akin, Filiz Sahin, Onuralp Yucel, Gultekin Goller
|On-Site Speaker (Planned)
ZrB2-ZrC-SiC composites were prepared by spark plasma sintering (SPS) at temperatures of 1750°C for 5 min under a pressure of 40 MPa. Densification, microstructural, mechanical properties and oxidation behavior of the composites were investigated. Fully dense ZrB2-ZrC-SiC composites with a relative density of more than 99% were obtained at 1750°C. Vickers hardness of ZrB2-ZrC-SiC composites decreased with increasing ZrC content from 30 to 40 vol%, and composite containing 60 vol% ZrB2, 20 vol% ZrC and SiC sintered at 1750°C had the highest value of 20.1 GPa. The crack mode for the same composite was zigzag, and resulted in remarkable crack deflections and the highest fracture toughness value of 5.3 MPa•m1/2. Oxidation of composites resulted in formation of protective layered oxide structures consisted of ZrO2 and Si-O rich layer in the form of SiO2 or SiO, and normalized mass change results increased with increasing oxidation temperature.