Comparative analysis of initial state in inhomogeneous rods

Abstract

The development and improvement of models of inhomogeneous bodies in the presence of residual stress and deformation fields plays an important role in the mechanics of deformable solid body. From the viewpoint of practical applications, one of the most prospective inhomogeneity type is the class of functionally graded composites (FGC), which material properties vary depending on coordinates. The gradient of properties in such materials is due to the inhomogeneous chemical composition, or the microstructure, or the atomic order. Research on beam-like FGC is the very first global step of exploration of FGC properties. A key question in the problem of monitoring of technical conditions of an object is often a question of proper selection of material’s damage characteristics detectiontechnique, and conducting a set of corresponding experimental investigations. A failure under loading belowthe allowable one is often due to unaccounted preliminary state (PS). It is important to provide the analysis of different types of inhomogeneity of material properties and PS factors (including residual stress and deformations) on dynamic characteristics. In the present paper the effect of various types of PS on acoustical characteristics spectrum (eigenfrequencies, frequency-response functions) is analyzed in FGC-beams. In the framework of the Timoshenko model, such PS factors are considered as residual stress, residual deflection, and residual angle of rotation of the principal axe of the beam due to bending. The computational experiments are conducted and analyzed. Refs 19. Figs 4.