Use of Ring Sample for High-Pressure Torsion and Microstructural Evolution with Equivalent Strain

Yuki Ito; Yosuke Harai; Tadayoshi Fujioka; Kaveh Edalati; Z. Horita

doi:10.4028/www.scientific.net/MSF.584-586.191

Paper Titles

High Strain Rate Superplasticity in a Zr and Sc Modified 7075 Aluminum Alloy Produced by ECAP
p.164

Influence of Number of Passes in ECAP on Superplastic Behavior in a Magnesium Alloy
p.170

The New Approach to Produce Al Sheets with UFG Structure Using SPD Processing
p.176

Grain Refinement and Deformation Behavior of Ultrafine Grained Pd and Pd-Ag Alloys Produced by HPT
p.182

Use of Ring Sample for High-Pressure Torsion and Microstructural Evolution with Equivalent Strain
p.191

Comparative Possibilities of Different X-Ray Methods by Study of SPD Metal Materials
p.197

Mechanical Behavior of Nanocrystalline Palladium at High Strains and High Strain Rates
p.203

Chemical Sensitive Positron-Annihilation Study of Amorphization and Nanocrystallization Processes by Repeated Roll Bonding
p.209

Microstructure and Indentation Size-Effect in Pure Niobium Subjected to SPD via ECAP and HPT
p.215

HomeMaterials Science ForumMaterials Science Forum Vols. 584-586Use of Ring Sample for High-Pressure Torsion and...

Use of Ring Sample for High-Pressure Torsion and Microstructural Evolution with Equivalent Strain

Abstract:

This study introduces a process of high-pressure torsion (HPT) using ring samples and compares with the results of conventional disk HPT. Both types of HPT were conducted at room temperature on pure Al and pure Cu. The microhardness was measured along the diameters of the disks and rings. Microstructures were examined using transmission electron microscopy. When hardness values were plotted against equivalent strain, all data points fell on a single line for each material. There was a hardness maximum for pure Al but no such a maximum was present in pure Cu. In pure Al, many dislocations were visible within grains up to the equivalent strain corresponding to the hardness maximum but beyond this strain, grains with low dislocation density appear. All materials exhibited steady state where the hardness remains constant with respect to imposed equivalent strain. This study concludes that use of ring samples is effective as an alternative to the disk samples.