Differential hysteresis loop of Ba

0.95

Sr

0.05

TiO

3

ferroelectric ceramics has been measured. It is found that the polarization fatigue in BST ceramics can be divided into three stages. The first stage when reversal number

N

is between 10

5

to 10

6

is dominated by aged effects. In the second stage where

N

is from 10

6

to10

8

fatigue effect appears. In the third stage when

N

is larger than 10

8

the sample is almost totally fatigued and can not be considered as a ferroelectrics.