A Decrease of Residual Stresses in the Elastic-Plastic-Creep Medium at Temperature Influence

Abstract

Within the linear theory of elastic-plastic body we carried out the modeling of technological process of annealing: slow heating stage, the holding stage under constant temperature and slow cooling step. Holding stage is simulated with consideration of creeping properties of materials. Boundary value problems are examined and patterns responsible for the removal of residual stresses at temperature influence are described. An analytical solution is found. It is proved that the holding stage is essential for describing the process of residual stress relief.

Relieving of Residual Stresses in Metal Workpieces at High and Low Temperatures

“…, the components of elastic deformations rr e and θθ e are determined by dependence Eq. 4 provided that p rr e and p e θθ will change: is formed in the medium, where 3 r -is the boundary of this area [8]. The level of residual stresses presented in Fig.…”

“…On the basis of Eq. 1-2, as in [6,7], the residual stresses were calculated [8]. A necessary condition was the static determinability of the plastic flow process [12,13].…”

“…1. Residual stresses were superimposed on the newly applied load (heating), and this caused an increase in the level of residual stresses [8,16]. In [16], on the basis of the linear viscoelastic Voigt model under conditions of a change in the yield stress of the material with increasing temperature, an increase in stresses was also established, leading to undesirable effects -repeated plastic flows.…”

“…In this article, within the framework of solid mechanics, the process of removing residual stresses in metal workpieces under low-temperature [6] and high-temperature action [7] is modeled. Boundary-value problems are examined and here are described (using the example of a hollow sphere with previously accumulated irreversible deformations [8]) regularities which are responsible for removing residual stresses for processing modes: high-temperature heatingcooling, high-temperature heating -holding -cooling, low-temperature heating -holding -cooling. Modeling was carried out by a quasi-static process of additional deformation with slow heating, holding at a certain temperature, and slow cooling.…”

Mathematical Modeling of the Technological Process of Residual Stresses Relief in Metals at Low-Temperature Exposure

“…The simulation results of high-temperature annealing are presented in [3]. On the example of a hollow sphere with accumulated irreversible deformations [4], in the framework of linear elasticplastic body, there is shown a decrease in residual stresses.…”