Influence of Cyclic Loading on Physical and Mechanical Properties of Thin-Film Membrane Structures

Abstract

The principle of modifying the mechanical properties of thin-film membrane structures of arbitrary shape by a non-contact method was proposed, implemented and explained for the first time. The idea was tested on a thin-film aluminum membrane formed by the magnetron method on a silicon substrate. The external influence was carried out through a cyclic load in the form of releasing and supplying excess air pressure to the membrane. As a result of repeated impacts, the physical properties of materials (grain size and roughness) and mechanical properties (internal mechanical stresses and critical overpressure) change. Changing the magnitude of residual mechanical stresses in the membrane material allows the formation of a surface with the required curvature value. In this work, after a cyclic load with a pressure equal to half the critical pressure, the following effects were revealed: the deflection of the membrane in the absence of external influence increased by more than an order of magnitude, the structure passed into a plastic type of deformation, the critical burst pressure decreased by several tens of percent. The use of this methodology makes it possible to create new materials with unique mechanical properties.