Effect of Sintering Temperature on Pore Structure and Mechanical Properties of Ti600 Alloy Foam

Porous titanium foams were fabricated from Ti600 high-temperature alloy powder (Ti-6Al-2.8Sn-4Zr-0.5Mo-0.4Si-0.1Y) via the powder metallurgy route, utilizing urea as a space holder. The effects of sintering temperature (1100–1400 °C) on the microstructure, porosity, and mechanical properties were systematically investigated using optical microscopy, scanning electron microscopy (SEM), and uniaxial compression tests. With increasing sintering temperature, the pore walls became progressively denser, resulting in a significant decrease in porosity from 67.61% at 1100 °C to 61.31% at 1400 °C. The average pore size also consistently decreased, reaching 1.194 mm at 1400 °C. The compressive strength increased steadily with temperature, peaking at 82.08 MPa at 1300 °C before slightly declining to 78.20 MPa at 1400 °C due to over-sintering. Similarly, the Young's modulus reached an optimum value of 1.735 GPa at 1300 °C, then marginally decreased to 1.719 GPa at 1400 °C, attributed to grain coarsening. The energy absorption efficiency also peaked at 1300 °C with a value of 28.131 MJ/m3. Consequently, under the present experimental conditions, 1300 °C was identified as the optimal sintering temperature, yielding well-densified pore walls and a uniform pore distribution, resulting in superior compressive strength and energy absorption capacity.