Laser shockwave sintering of nanopowders of yttria-stabilized zirconia

Mechanical (non-thermal) sintering behavior of nanopowder green compacts of yttria-stabilized zirconia (YSZ) using laser-induced shockwaves was investigated. Results showed 15% improvement in density and 44% increase in hardness for the single shock. In addition, thermal conductivity of LSP samples was much lower (1 W/m K) than thermally-sintered, micro-powder samples (2 W/m K) inferring that the presence of nanoparticles at the pores limits the mean free paths of phonons and photons. Analytical model results provided a peak shock pressure of 4.34 GPa, plastic strain of 0.02 on the surface layer, and shockwave penetration depth of 0.25 mm. Multiple shocks have potential to substantially increase the mechanical and thermal properties of YSZ.