Cargando…

Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel

The “torsion and annealing” grain boundary modification of pure nickel wires with different diameters was carried out in this paper. The effects of torsional cycles as well as unidirectional/bidirectional torsion methods on grain boundary characteristic distribution and plasticity were investigated....

Descripción completa

Detalles Bibliográficos
Autores principales: Lin, Yao, Liu, Shan, Wu, Tao, Wang, Guangchun
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8745951/
https://www.ncbi.nlm.nih.gov/pubmed/35009386
http://dx.doi.org/10.3390/ma15010236
_version_ 1784630467598745600
author Lin, Yao
Liu, Shan
Wu, Tao
Wang, Guangchun
author_facet Lin, Yao
Liu, Shan
Wu, Tao
Wang, Guangchun
author_sort Lin, Yao
collection PubMed
description The “torsion and annealing” grain boundary modification of pure nickel wires with different diameters was carried out in this paper. The effects of torsional cycles as well as unidirectional/bidirectional torsion methods on grain boundary characteristic distribution and plasticity were investigated. The fraction of special boundaries, grain boundary characteristic distributions and grain orientations of samples with different torsion parameters were detected by electron backscatter diffraction. Hardness measurement was conducted to characterize the plasticity. Then, the relationship between micro grain boundary characteristics and macro plasticity was explored. It was found that the special boundaries, especially Σ3 boundaries, are increased after torsion and annealing and effectively broke the random boundary network. The bidirectional torsion with small torsional circulation unit was the most conducive way to improve the fraction of special boundaries. The experiments also showed that there was a good linear correlation between the fraction of special boundaries and hardness. The plasticization mechanism was that plenty of grains with Σ3 boundaries, [001] orientations and small Taylor factor were generated in the thermomechanical processes. Meanwhile, the special boundaries broke the random boundary network. Therefore, the material was able to achieve greater plastic deformation. Moreover, the mechanism of torsion and annealing on the plasticity of pure nickel was illustrated, which provides theoretical guidance for the pre-plasticization of nickel workpieces.
format Online
Article
Text
id pubmed-8745951
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-87459512022-01-11 Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel Lin, Yao Liu, Shan Wu, Tao Wang, Guangchun Materials (Basel) Article The “torsion and annealing” grain boundary modification of pure nickel wires with different diameters was carried out in this paper. The effects of torsional cycles as well as unidirectional/bidirectional torsion methods on grain boundary characteristic distribution and plasticity were investigated. The fraction of special boundaries, grain boundary characteristic distributions and grain orientations of samples with different torsion parameters were detected by electron backscatter diffraction. Hardness measurement was conducted to characterize the plasticity. Then, the relationship between micro grain boundary characteristics and macro plasticity was explored. It was found that the special boundaries, especially Σ3 boundaries, are increased after torsion and annealing and effectively broke the random boundary network. The bidirectional torsion with small torsional circulation unit was the most conducive way to improve the fraction of special boundaries. The experiments also showed that there was a good linear correlation between the fraction of special boundaries and hardness. The plasticization mechanism was that plenty of grains with Σ3 boundaries, [001] orientations and small Taylor factor were generated in the thermomechanical processes. Meanwhile, the special boundaries broke the random boundary network. Therefore, the material was able to achieve greater plastic deformation. Moreover, the mechanism of torsion and annealing on the plasticity of pure nickel was illustrated, which provides theoretical guidance for the pre-plasticization of nickel workpieces. MDPI 2021-12-29 /pmc/articles/PMC8745951/ /pubmed/35009386 http://dx.doi.org/10.3390/ma15010236 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Lin, Yao
Liu, Shan
Wu, Tao
Wang, Guangchun
Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel
title Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel
title_full Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel
title_fullStr Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel
title_full_unstemmed Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel
title_short Effects of Unidirection/Bidirection Torsional Thermomechanical Processes on Grain Boundary Characteristics and Plasticity of Pure Nickel
title_sort effects of unidirection/bidirection torsional thermomechanical processes on grain boundary characteristics and plasticity of pure nickel
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8745951/
https://www.ncbi.nlm.nih.gov/pubmed/35009386
http://dx.doi.org/10.3390/ma15010236
work_keys_str_mv AT linyao effectsofunidirectionbidirectiontorsionalthermomechanicalprocessesongrainboundarycharacteristicsandplasticityofpurenickel
AT liushan effectsofunidirectionbidirectiontorsionalthermomechanicalprocessesongrainboundarycharacteristicsandplasticityofpurenickel
AT wutao effectsofunidirectionbidirectiontorsionalthermomechanicalprocessesongrainboundarycharacteristicsandplasticityofpurenickel
AT wangguangchun effectsofunidirectionbidirectiontorsionalthermomechanicalprocessesongrainboundarycharacteristicsandplasticityofpurenickel