Finite Element Modelling of High-Pressure Torsion: An Overview

Abstract

Finite element modelling (FEM) has been extensively performed to study the flow process, the distribution of hydrostatic stress and the temperature rise in materials processed by high-pressure torsion (HPT). This overview provides a summary and a critical assessment of the most important findings obtained by means of these FEM simulations which permitted a better understanding about the microstructural evolution during processing by HPT. For convenience, FEM investigations focused on examining the nature of the HPT facility, the plastic flow, the hydrostatic pressure and the temperature evolution in HPT processing were separated into different topics. It is shown the distributions of strain, temperature and hydrostatic pressure along the disc diameter depend upon different factors such as the configuration of the HPT facility and the dimensions of the processed sample. [

The Stability of Oxygen‐Free Copper Processed by High‐Pressure Torsion after Room Temperature Storage for 12 Months

“…[13] One parameter that may produce recovery is the increase in temperature that occurs during the HPT process which has been well documented by finite element modeling. [16,43] The results from this modeling show that the temperature increases both due to the heat generated during the plastic deforming of the sample and due to the friction inherent in the material flow during the anvil rotation. Accordingly, it is important to investigate the influence of a temperature rise on the occurrence of recovery in the present study.…”

An Investigation of Strain‐Softening Phenomenon in Al–0.1% Mg Alloy during High‐Pressure Torsion Processing

“…Several reports investigated the temperature rise due to heat generated during plastic deformation and friction inherent in the material flow during the anvil rotation through finite element modeling. [37][38][39] Recent investigations examined the temperature rise and corresponding microstructure changes in Al, Ag, and Cu during HPT processing and it was concluded that the temperature rise is of only minor significance in initiating dynamic recrystallization. [40,41] Accordingly, the recrystallization phenomenon in Al-0.1% Mg alloy appears to be mainly due to the formation of large fractions of lattice defects from the heavy shear strains.…”

“…A temperature rise during HPT processing is a factor that may produce recovery and recrystallization in addition to the plastic strain applied on the material. Several reports investigated the temperature rise due to heat generated during plastic deformation and friction inherent in the material flow during the anvil rotation through finite element modeling . Recent investigations examined the temperature rise and corresponding microstructure changes in Al, Ag, and Cu during HPT processing and it was concluded that the temperature rise is of only minor significance in initiating dynamic recrystallization .…”

<i>In Situ</i> Synchrotron X-ray Analysis: Application of High-Pressure Sliding Process to Ti Allotropic Transformation

“…Close analysis revealed that the real pressure applied on the sample was ³4 GPa as discussed later. It should be noted that diamond (111) peaks are visible in the X-ray profiles and this is because the space between the upper and lower anvils was reduced due to the loading so that the X-ray now illuminated on the sample together with the anvils. It should be also noted that the presence of the ¢ phase was not expected for the conditions of pressure and temperature adopted in this study based on the first-principle calculation reported earlier.…”