Nonstationary waves in an inelastic disk under impulsive radial loading

Abstract

Nonstationary axisymetric waves in a disk excited by an impulsive radial load are analyzed numerically. The nonlinear deformation of the material is described by the Bodner-Partom model. The model parameters are derived from experimental data for samples subjected to tension followed by compression over a wide range of strain rates. The temporal and spatial characteristics of the wave process are studied. The influence of hardening on wave focusing and residual strain distribution is examined Keywords: nonstationary waves, physically nonlinear material, disk, impulsive loading, finite-element methodIntroduction. Many structural members in modern technology are cylindrical bodies that, while in service, experience impulsive loads, which induce inelastic residual strains. Strength evaluation of such structures calls for stress-strain analysis methods that would allow for the rheological behavior of the material, the geometry of the body, and nonstationary loads acting on it.Analysis of residual stress-strain state (SSS) of bodies under impulsive loading is of considerable theoretical and practical interest [20,21]. These problems play a crucial role in the fatigue crack arresting techniques currently under development. They use an impulsive, explosion load with energy focused at the crack tip to induce compressive residual stresses and plastic strains [10].Research in this field is also motivated by the needs of explosion welding [5]; impulsive straightening of thin-walled structures, including welded ones [6,27]; surface hardening [15,22]; etc. In all these applications, the prime objective of calculations is to determine the appropriate process parameters. New technologies also require studying the influence of dynamic processes on the kinetics of microstructural transformations in materials [18, 28, etc].In studying nonstationary dynamic processes, reliable results can be obtained by accomplishing two basic tasks. One is to select and specify constitutive equations for fast (10 10

Electrically Excited Nonstationary Vibrations of Thin Circular Piezoelectric Plates

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Numerical solution to the initial-boundary-value problem of electroelasticity for a radially polarized hollow piezoceramic cylinder

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