Zirconia fibre mats prepared by a sol-gel spinning technique

Fine grained, polycrystalline, stabilized zirconia (with 10 wt.% Y2O3) fibre mats having a web-like structure were fabricated directly during synthesis by a sol-gel spinning technique using a multi-orifice spinneret. Points of fusion in gel fibre mats helped in the formation of a web-like fibrous body having reasonable strength and very little dust formation after calcination. Strong and resilient fibres with diameters in the range 3–10 micron were obtained by a single-step sol-gel method from spinnable acetate sols devoid of organics as the binder aid. The Y2O3 additive in the fibre mats helped to retain the tetragonal phase even at 1600°C by inhibiting grain growth. The health hazard involved with airborne fibres was significantly minimized in the developed zirconia mats by applying sol-gel coatings on their surfaces followed by calcination. The resulting samples exhibited reasonably coherent coatings by anchoring loose surface fibres in a network of zirconia.