Detection of ceramic stress intensity factor based on digital holography

This study investigates the application of digital holography in investigating fracture problems of the ceramic material magnesium oxide under three-point bending fracture experiments. A digital holographic optical path system was constructed for this purpose. Three-point bending experiments were performed on magnesium oxide samples using the system, with holograms of the specimens recorded both before and after the application of loads. By utilizing the angular spectrum diffraction reconstruction algorithm, we obtained the complex amplitude of the object wave under varying load conditions and computed the phase changes of the object wave corresponding to different loads. Subsequently, we derived interference fringes from these phase changes, enabling the measurement of the stress intensity factor of magnesium oxide through holographic interferometry and plane stress theory. A comparison of the experimental measurements with theoretical values demonstrates that digital holographic technology is a viable method for measuring the stress intensity factor of ceramic magnesium oxide.