Mechanical properties of a 20 vol % SiC whisker-reinforced, yttria-stabilized, tetragonal zirconia composite at elevated temperatures

Abstract

The high-temperature deformation behavior of a SiC whisker-reinforced, yttria-stabilized, tetragonal zirconia polycrystalline composite containing 20 vol % SiC whiskers (SiC/Y-TZP) has been investigated. Tensile tests were performed in vacuum at temperatures from 1450 °C to 1650 °C and at strain rates from 10−3 to 10−5 s−1. The material exhibits useful high-temperature engineering properties (e.g., ∼100 MPa and 16% elongation at T = 1550 °C and at a strain rate of ∼10−4 s−1). The stress exponent was determined to be n ≍ 2. Scanning electron microscopy was used to characterize the grain size and morphology of the composites, both before and after deformation. The grain size in the composite was initially fine, but coarsened at the test temperatures; both dynamic and static grain growth were observed. The morphology of ceramic reinforcements appears to affect strongly the plastic deformation properties of Y-TZP. A comparison is made between the properties of monolithic Y-TZP, 20 wt. % Al2O3 particulate-reinforced Y-TZP (Al2O3/Y-TZP), and SiC/Y-TZP composites.

Creep Mechanisms in Multiphase Ceramic Materials

“…Most of the creep studies on this class of materials have been performed using Al 2 O 3 reinforced with SiC whiskers. However, SiC whiskers embedded in other matrices, such as mullite, 46 MoSi 2 , 47,48 ZrO 2 , 49,50 and ZrO 2 -toughened Al 2 O 3 (ZTA) 51,52 also have been studied. † These composites consist almost entirely of crystalline phases, although some glass often is present along the whisker-matrix interface after processing.…”

Hard, tough and strong ZrO2–WC composites from nanosized powders

“…Amongst the composite systems investigated are mullite-ZrO 2 , 2 Si 3 N 4 -ZrO 2 , 3 TiB 2 -ZrO 2 4-7 and Ti(C, N)-ZrO 2 . 8,9 Other reported systems in which the ZrO 2 is present as the matrix phase includes ZrO 2 -Al 2 O 3 -TiC, 10 ZrO 2 -SiC, 11 ZrO 2 -Cr 2 O 3 , ZrO 2 -Cr 3 C 2 and ZrO 2 -Cr 7 C 3 . 12 Recently, ZrO 2 -based composites with hard TiB 2 , TiCN, TiN and TiC secondary phase additions were described.…”

Effect of Particle Morphology on Sinterability of SiC‐ZrO2 in Microwave

“…One of the applications of SiC is in gas turbines. Mechanical properties of SiC, especially fracture toughness, can be improved by the addition of other phases into a material matrix to form a composite structure [8][9][10][11][12]. SiC-based ceramics are generally produced by cold die compaction with subsequent sintering or by hot isostatic pressing and finishing [13].…”