Mechanical properties of particle reinforced titanium and titanium alloys

Abstract

Titanium grade 2, Ti-6A1-4V and Ti-6Al-6V-2Sn unreinforced and reinforced with 10-15 vol.% SiC particles, 5 vol.% TiB whiskers and 12-20 vol.% TiC are characterized by compression tests, micro-, macro- and nano-hardness measurements, and X-ray diffraction. The measured Young's moduli up to 350°C were found to be described using the Halpin Tsai model for the TiC and of TiB reinforced materials (aspect ratio of 1 and 100, respectively). The strengthening by SiC addition is attributed to matrix strain hardening due to the thermal misfit between the matrix and the reinforcement. The strengthening of TiC reinforced material is attributed to interstitial C dissolved in the alpha phase proved with the nanohardness results. TiB precipitates produce strengthening by grain refinement and dispersion hardening. The presence of 1 wt.% of C in the matrix also should be the reason for higher Young's modulus and strengthening.