抄録
In this paper, the sensing conditions for sensitive acoustic emission (AE) signals are mentioned and AE source position method for improvement accuracy is discussed, and the detection of crack failure of silicon nitride ceramic bearings in rolling contact is carried out by this method.
AE sensor sensitivity is estimated by the effect of mounting conditions of AE sensor which are holding sensor pressure and couplant between sensor and specimen. As a result, sensitive AE signal is obtained when the pressure should be greater than 1.2MPa using oil or grease as the couplant. It is possible to determine the position of AE source accurately by mesuring the arrival time difference of the second peak point of each wave between sensors.
In the experimental result of the rolling contact bearings, error of the surface crack position is 1.56mm. This value is a satisfactory accuracy.