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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,.%), and loading temperature (20-1300°C) on the mechanical properties of Ti 3 SiС 2 /TiС, Ti 3 AlС 2 /TiС, and Ti 4 AlN 3 /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: Ti 3 AlС 2 /TiС, Ti 4 AlN 3 /TiN, and Ti 3 SiС 2 /TiС. Temperature-strain and force boundaries of their existence in the deformed state are established. Among all porous nanolaminate composites investigated, Ti 3 SiС 2 /TiС is the most optimal in respect to porosity, content of the other phase, and strength: 24% porosity and 30 vol.% titanium carbide.

reaction sintering in compact and porous states. The regularities, specific features, and mechanisms of deformation and fracture processes are established for each material within the temperature range 20-1300°C. The temperature-strain and force boundaries of their existence in the plastic state are determined. The comparative analysis of the mechanical properties of nanolaminates is performed. It is shown that the strength characteristics of nanolaminates and their strain and creep resistance at medium and high temperatures increase in the following sequence: Ti 3 AlC 2 -Ti 4 AlN 3 -Ti 3 SiC 2 . The obtained picture of high-temperature properties of these materials is explained. It is shown that the procedure of prestraining of a porous material by ε = 4-8% may result in a significant increase in its specific high-temperature strength up to values higher than those typical of the compact material.Keywords: sintered titanium nanolaminates, porosity, compression strength, indentation, energy of interatomic bonds, relative testing temperature. Notation θ -porosity of a material H A -Meyer microhardness HV -Vickers macrohardness ΔHV rel -relative decrease in the high-temperature macrohardness on holding under a load P =10 N for t = 60 min ΔHV rel −1 -measure of high-temperature strength in the process high-temperature macroindentation Δh -level of creep in the process of microindentation at room temperature (the depth of penetration of the indentor) h c -level of creep in the process of high-temperature macroindentation (the depth of penetration of the indentor) σ pr -proportionality limit in uniaxial compression 624 0039-2316/06/3806-0624 -specific strength in uniaxial compression σ 5 -strength of the material in uniaxial compression for a level of strain ε = 5% σ ρ 5 -specific strength in uniaxial compression for a level of strain ε = 5% ( ) ( ) σ ρ σ ρ 5 por comp 5 -specific strength of the porous material relative to the specific strength of the compact material in uniaxial compression for a level of strain ε = 5%Introduction. Materials based on titanium are among the most promising structural materials combining low density, low-temperature technological efficiency, and high characteristics of high-temperature strength and heat resistance. In recent years, significant attention of the researchers is given to a new class of materials called nanolaminates (they are also called MAX compounds) [1][2][3][4][5][6][7][8]. The nanolaminates are ternary compounds described by the formula M AX