Abstract: The electrostrictive strain, hysterestic (S～ E) nature and remanent strain effect were investigated in their diffuse phase transition temperature
rang for two kinds of La-doping PMN-based ceramics with the diffuse phase transition center temperature 40℃ and 65℃ respectively.
The experimental results show that for the material with diffuse phase transition center temperature 40℃, its strain and hysteresis decrease as temperature
increases in the range of --10℃ to 60℃ driving by 0～1kV/mm one direction field, and for the other material whether driving by ±1kV/mm AC field or 0～1kV/mm one direction field the strains exhibit a
peak value with temperature change from 13℃ to 41℃, the remanent strain and hysteresis decrease monotonically with temperature increase. Above
experimental results were also explained in detail.

Key words: PMN-based ceramics, electrostriction, diffuse phase transition