Functional materials based on the effect of mechanoluminescence for monitoring the state of load-bearing structures

Abstract

Researches of light-generating converters based on zinc sulfide allowed us to describe the physical nature of the light signal. The description of the physical nature of light generation by semiconductors is based on the band theory of conductivity. This allowed us to determine the conditions for the possibility of registering mechanical impacts using mechanoluminescent pulse pressure sensors. One of the important conditions, as it turned out, is the presence of manganese impurities in the material, which become centers of light emission. Also a necessary condition for the appearance of luminescence is the hardness of the sensor element, it facilitates the transfer of mechanical stress to the crystal lattice of mechanoluminescent material and the changes in it with the release of energy as light. This property of these materials allows them to operate in generator mode and convert mechanical action into an optical signal without additional energy sources. As a result, theoretical and experimental data on the possibility of detecting pulsed mechanical action using distributed mechanoluminescent converters were obtained. As one of the directions of application of such converters, it is proposed to create composite materials with the insertion of light-conducting fibers with longitudinal light transmission, covered with mecanoluminophore particles. This will allow to create composite materials with a self-diagnosis function and the ability to connect to optical data channels for continuous monitoring of the technical condition of load-bearing structures of buildings. Such materials are devoid of such disadvantages as: the need for power supply or a reference light stream, sensitivity to electromagnetic interference, and a low degree of embeddability in the structure, inherent in the devices currently used.