Zirconia fibre mats prepared by a sol-gel spinning technique

Fine grained, polycrystalline, stabilized zirconia (with 10 wt.% Y2O3) fibr e mats having a web-like structure were fabricated directly during synthesi s by a sol-gel spinning technique using a multi-orifice spinneret. Points o f fusion in gel fibre mats helped in the formation of a web-like fibrous bo dy having reasonable strength and very little dust formation after calcinat ion. Strong and resilient fibres with diameters in the range 3-10 micron we re obtained by a single-step sol-gel method from spinnable acetate sols dev oid of organics as the binder aid. The Y2O3 additive in the fibre mats help ed to retain the tetragonal phase even at 1600 degreesC 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 th eir surfaces followed by calcination. The resulting samples exhibited reaso nably coherent coatings by anchoring loose surface fibres in a network of z irconia. (C) 2001 Elsevier Science Ltd. All rights reserved.