MECHANICAL PROPERTIES OF POROUS Ti3SiC2/TiC, Ti3AlC2/TiC, AND Ti4AlN3/TiN NANOLAMINATES AT 20 TO 1300°C

The microindentation, macrohardness, and uniaxial compression methods are used to examine the effect of porosity (5-35%), content of the other phase (TiC or TiN, 5-70 vol.%), and loading temperature (20-1300 degrees C) on the mechanical properties of Ti3SiC2/TiC, Ti3AlC2/TiC, and Ti4AlN3/TiN nanolaminate composites produced by reaction sintering of powder mixtures. A comparative analysis of the mechanical properties shows that the strength of the materials increases in the following sequence: Ti3AlC2/TiC, Ti4AlN3/TiN, and Ti3SiC2/TiC. Temperature-strain and force boundaries of their existence in the deformed state are established. Among all porous nanolaminate composites investigated, Ti3SiC2/TiC is the most optimal in respect to porosity, content of the other phase, and strength: 24% porosity and 30 vol.% titanium carbide.