Study On Structure Of Graphene Diaphragm Applied To Micro-acoustic Detection

Sound reconnaissance technology is a technology that search targets and monitor their actions through capturing sound signals.The sound reconnaissance technology had not gain adequate development,due to the obvious attenuation of sound wave in the air with the increase of propagation distance and the inability of traditional microphone pickup to perceive weak sound.The air is full of available sound information,and different military and civilian targets will send out sound signals with obvious characteristics.However,due to the high detection limit of the existing microphone pickups,these sound information have not be effectively utilized.In order to solve the problem of long-range sound detection,here,we revealed a graphene-vibro-diaphragm based micro sound detection technology base on pickup by the theoretical and experiment methods in this paper.The development and application of this technology will subvert the range and distance of sound detection of traditional microphone pickup,expand the form of military and civil reconnaissance,provide asymmetric reconnaissance advantages,and meet the relevant needs of search and rescue,security,counter-terrorism,police surveillance,advanced recording equipment and other fields.Molecular dynamics simulation was used to calculate the potential energy difference between the curved graphene model and the flat plate model.The bending stiffness of multilayer graphene diaphragms was obtained.A linear empirical formula of the bending stiffness of graphene diaphragms versus the number of graphene layers is obtained.It was found that the bending stiffness of graphene diaphragms with different chirality had little difference.In this paper,the sensitivity of sound intensity detection of graphene vibro-diaphragm structure of different layers of graphene is calculated,and the tensile strength of ultra-thin graphene diaphragm is proved to meet the strength requirements of graphene vibro-diaphragm material,and the experimental verification is completed.In this paper,a large-size graphene diaphragm structure was fabricated,and a circuit for acquiring small sound signals was designed.The test results were in line with expectations.