Preparation of Undoped Lead Titanate Ceramics via Sol‐Gel Processing

Crack‐free, undoped PbTiO 3 ceramics were fabricated successfully using sol–gel‐synthesized powder prepared from chelated titanium alkoxide and lead acetate. The sintered ceramics, 8.3 mm in diameter and 6–8 mm thick, were 96% dense. In the present study, PbTiO 3 ceramics with excess lead (Pb:Ti = 1.1:1.0) had large grains, averaging 14.3 μm. Lower‐lead ceramics (Pb:Ti = 1.0:1.0 and 0.9:1.0) had smaller grains, averaging 1.8 μm. The PbTiO 3 ceramics with a high lead content cracked during sintering at 1150°C, whereas the other ceramics did not crack. Excess lead, in a more‐than‐stoichiometric ratio, promoted grain growth and caused disintegration of the ceramics. Therefore, uncracked PbTiO 3 ceramics apparently can be fabricated by avoiding excess lead, possibly because restricted grain growth in low‐lead ceramics causes low residual stress over many small grains during transition. The electrical properties measured in the present study for PbTiO 3 ceramics with a Pb:Ti ratio of 1:1 are d 33 = 35 pC/N, K 3 = 64, k p = 0.59, and k t ≈ 0.