Dynamic Calibration of Mechanoluminescent Materials for Shock Wave Field Measurement

This study aims to enable the quantitative application of mechanoluminescent materials in shock wave overpressure measurement. Existing quasi-static or low-frequency dynamic calibration methods fail to accommodate the transient loading characteristics of shock waves. To address this issue, the authors conducted a dynamic calibration study on ZnS:Mn²⁺ mechanoluminescent composite films. The authors prepared ZnS:Mn²⁺ powder via a high-temperature solid-state method and fabricated it into composite films. They established a shock-tube dynamic calibration system to synchronously acquire shock wave overpressure signals, mechanoluminescence images and spectra. They also proposed a mechanoluminescence intensity extraction method, with the standard light source method and spectral matching method as core components. Sixty calibration experiments were conducted at overpressures ranging from 0.1 to 2.0 MPa. The results showed that, for the film, the peak mechanoluminescence intensity exhibited a strong linear relationship with peak overpressure from 0.2 to 1.7 MPa. The calibration equation was I_peak= 44.702 P_peak + 15.052, with a coefficient of determination of 0.9933 and a linearity error of 5.81 percent. The film exhibited a sub-millisecond time-domain dynamic response, with a response latency of approximately 0.174 ms and a rise time of approximately 0.323 ms. Under repeated loading, irreversible mechanoluminescence degradation occurred, and the degree of degradation increased with rising peak overpressure. These calibration results demonstrate the feasibility of inverting shock wave peak overpressure from mechanoluminescence intensity, and provide an experimental basis for the application of mechanoluminescent materials to full-field visual measurement of shock wave overpressure.