Cargando…
High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing
Twin roll cast Al-Mn- and Al-Mn-Zr-based alloys were subjected to four passes of equal channel angular pressing. The resulting grain size of 400 nm contributes to a significant strengthening at room temperature. This microstructure is not fully stable at elevated temperatures and recrystallization a...
Autores principales: | , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2015
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5458924/ https://www.ncbi.nlm.nih.gov/pubmed/28793667 http://dx.doi.org/10.3390/ma8115401 |
_version_ | 1783241856825425920 |
---|---|
author | Málek, Přemysl Šlapáková Poková, Michaela Cieslar, Miroslav |
author_facet | Málek, Přemysl Šlapáková Poková, Michaela Cieslar, Miroslav |
author_sort | Málek, Přemysl |
collection | PubMed |
description | Twin roll cast Al-Mn- and Al-Mn-Zr-based alloys were subjected to four passes of equal channel angular pressing. The resulting grain size of 400 nm contributes to a significant strengthening at room temperature. This microstructure is not fully stable at elevated temperatures and recrystallization and vast grain growth occur at temperatures between 350 and 450 °C. The onset of these microstructure changes depends on chemical and phase composition. Better stability is observed in the Al-Mn-Zr-based alloy. High temperature tensile tests reveal that equal channel angular pressing results in a softening of all studied materials at high temperatures. This can be explained by an active role of grain boundaries in the deformation process. The maximum values of ductility and strain rate sensitivity parameter m found in the Al-Mn-Zr-based alloy are below the bottom limit of superplasticity (155%, m = 0.25). However, some features typical for superplastic behavior were observed—the strain rate dependence of the parameter m, the strengthening with increasing grain size, and the fracture by diffuse necking. Grain boundary sliding is believed to contribute partially to the overall strain in specimens where the grain size remained in the microcrystalline range. |
format | Online Article Text |
id | pubmed-5458924 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-54589242017-07-28 High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing Málek, Přemysl Šlapáková Poková, Michaela Cieslar, Miroslav Materials (Basel) Article Twin roll cast Al-Mn- and Al-Mn-Zr-based alloys were subjected to four passes of equal channel angular pressing. The resulting grain size of 400 nm contributes to a significant strengthening at room temperature. This microstructure is not fully stable at elevated temperatures and recrystallization and vast grain growth occur at temperatures between 350 and 450 °C. The onset of these microstructure changes depends on chemical and phase composition. Better stability is observed in the Al-Mn-Zr-based alloy. High temperature tensile tests reveal that equal channel angular pressing results in a softening of all studied materials at high temperatures. This can be explained by an active role of grain boundaries in the deformation process. The maximum values of ductility and strain rate sensitivity parameter m found in the Al-Mn-Zr-based alloy are below the bottom limit of superplasticity (155%, m = 0.25). However, some features typical for superplastic behavior were observed—the strain rate dependence of the parameter m, the strengthening with increasing grain size, and the fracture by diffuse necking. Grain boundary sliding is believed to contribute partially to the overall strain in specimens where the grain size remained in the microcrystalline range. MDPI 2015-11-12 /pmc/articles/PMC5458924/ /pubmed/28793667 http://dx.doi.org/10.3390/ma8115401 Text en © 2015 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons by Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Málek, Přemysl Šlapáková Poková, Michaela Cieslar, Miroslav High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing |
title | High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing |
title_full | High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing |
title_fullStr | High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing |
title_full_unstemmed | High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing |
title_short | High Temperature Deformation of Twin-Roll Cast Al-Mn-Based Alloys after Equal Channel Angular Pressing |
title_sort | high temperature deformation of twin-roll cast al-mn-based alloys after equal channel angular pressing |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5458924/ https://www.ncbi.nlm.nih.gov/pubmed/28793667 http://dx.doi.org/10.3390/ma8115401 |
work_keys_str_mv | AT malekpremysl hightemperaturedeformationoftwinrollcastalmnbasedalloysafterequalchannelangularpressing AT slapakovapokovamichaela hightemperaturedeformationoftwinrollcastalmnbasedalloysafterequalchannelangularpressing AT cieslarmiroslav hightemperaturedeformationoftwinrollcastalmnbasedalloysafterequalchannelangularpressing |