The Influence of Thermo-Plastic Processes on Materials Recovery

Abstract

The influence of thermo-plastic processes through methods of severe plastic deformations (SPD) and rolling carried out at ambient and cryogenic temperatures on recovery of two materials was investigated. The aim of this study was to insert strains to materials having middle and high stacking fault energy (SFE) in ambient and cryogenic temperature conditions, respectively and subsequently, through DSC method, to observe an influence of the storage energy on structural recovery of materials. As experimental materials were used oxygen free high conductivity copper (OFHC Cu) and C-Si steel which represent materials with middle and high stacking fault energy (SFE), respectively. The OFHC Cu was subjected to equal channel angular rolling (ECAR) by seven passes. ECAR is a method belonging to a SPD group. It was shown, five ECAR passes have a significant effect on material properties. The rolling performed at cryogenic temperatures using a laboratory duo rolling mill was carried out only once. This study implies that a recovery process (characterized by the mobility of structural defects) starts as follows: for OFHC Cu without ECAR and processed by 5thECAR passes: 0.31·Tmeltand 0.19·Tmelt, respectively, for C-Si steel processed by cryorolling: 0.095·Tmelt.

Austenitic Grain Size Effect on the Phase Transformation of a 7.0% Cr Steel for Forging

“…• grain size reduction • microstructure refinement • solution hardening • dislocation strengthening • precipitation hardening Grain size reduction method implies a lowering in materials ductility [6][7][8][9][10][11][12][13]. Solution hardening permits to enhance fatigue and high temperature behavior [14][15][16][17][18][19].…”

Material Recovery of OFHC Cu and FeSi Steel after Processing by Plastic Deformations

“…The review paper [14] is mostly aimed at the analyze of UFG metals and alloys through the DSC method. Only few research works deal with a study of steels by DSC techniques [15,16]. * corresponding author; e-mail: tibor.kvackaj@tuke.sk…”

The Effect of Cryo-Rolling and Annealing on Magnetic Properties in Non-Oriented Electrical Steel

“…The effect of plastic deformation on the properties of non-oriented electrical steels has a significant difference in rolling at cryo conditions and ambient temperature [11][12][13][14]. The progressive methods for this material are currently, like rolling at the cryo conditions, not explored.…”