Strengthening Ti3AlC2 by In Situ Synthesizing Ti3AlC2–Y4Al2O9 Composites

Abstract

Ti3AlC2 has low density, high elastic modulus, quasi‐ductility, and excellent oxidation resistance. However, its relatively low strength needs to be improved. In this study, dense Ti3AlC2–Y4Al2O9 composites (containing 2.5, 5, and 7.5 wt% Y4Al2O9) were synthesized by hot pressing/solid‐liquid reaction using Ti, Al, C, and Y2O3 as initial materials. We investigated the in situ formation process of Y4Al2O9, and studied the change of microstructure and optimization of mechanical properties of the Ti3AlC2–Y4Al2O9 composites. The grain size and aspect ratio of Ti3AlC2 grains are significantly reduced in Ti3AlC2–Y4Al2O9 composites, which is the source of higher strength from room temperature to elevated temperatures. The Ti3AlC2‐5 wt%Y4Al2O9 composite shows better optimization in its mechanical properties than other studied composites. In addition, there is an improvement in strength without debit in toughness of the composite.