On the use of microbend fiber-optic sensor in material characterization

A new microbend fiber-optic sensor has been developed and applied to static and, dynamic fracture problems and impact detection. The static and dynamic calibration of this sensor is described. The sensor was made using a multimode fiber and the response of the sensor was studied and optimized. It has a strain sensitivity (gage factor) of over 28 with wide dynamic range and high frequency response. A single edge notched specimen was used with this sensor to determine both the static and dynamic stress intensity factors. The experimental results match well with the theoretical predictions and with the results obtained using electrical strain gages