Optical Response and Application of Mechanoluminescent Film of ZnS:Cu under Impact Pressure

Mechanoluminescent materials are widely used in stress sensing, recording and other fields because of their strong luminescence brightness, high force sensitivity, good stability and no need for external bias or ultraviolet irradiation. However, little research has been conducted on dynamic impact response of mechanoluminescent materials. ZnS:Cu powder was prepared by high temperature solid state sintering, and characterized by X-ray diffractometer, Raman spectrometer, scanning electron microscope and X-ray photoelectron spectroscopy. The results show that ZnS:Cu powders have a wurtzite structure, and the average particle size is about 20 μm. The mechanoluminescent film of approximately 50 μm thickness was coated on the target plate by mixing ZnS:Cu powder and sodium silicate. In addition, the plane-plate impact experiments show that the output voltage signal induced by ZnS:Cu mechanoluminescent film has a linear relationship with the impact pressure, which is consistent with the theoretical analysis. Finally, two testing methods based on mechanoluminescent film are proposed. The multi-point impact pressure test method can be used for the distributed measurement of detonation pressure produced by small-scale and large-scale explosive charges, and the shock wave arrival time test method can be used for the measurement of shock wave velocity, shock wavefront shape and other parameters.