No Cover Image

E-Thesis 158 views 61 downloads

Environmentally assisted fatique crack development in aluminium-based metal matrix composites. / Julia Diane Shields

Swansea University Author: Julia Diane Shields

Abstract

"Aluminium alloys have been used successfully in a variety of commercial systems due to their unusual combination of properties. These include low density, good corrosion resistance and excellent mechanical properties. However, they also have disadvantages which include a low resistance to frac...

Full description

Published: 2003
Institution: Swansea University
Degree level: Master of Philosophy
Degree name: M.Phil
URI: https://cronfa.swan.ac.uk/Record/cronfa42436
first_indexed 2018-08-02T18:54:42Z
last_indexed 2019-10-21T16:47:49Z
id cronfa42436
recordtype RisThesis
fullrecord <?xml version="1.0"?><rfc1807><datestamp>2018-08-16T14:39:02.9105634</datestamp><bib-version>v2</bib-version><id>42436</id><entry>2018-08-02</entry><title>Environmentally assisted fatique crack development in aluminium-based metal matrix composites.</title><swanseaauthors><author><sid>0c8485dbbe0b3abe40e412889096e828</sid><ORCID>NULL</ORCID><firstname>Julia Diane</firstname><surname>Shields</surname><name>Julia Diane Shields</name><active>true</active><ethesisStudent>true</ethesisStudent></author></swanseaauthors><date>2018-08-02</date><abstract>"Aluminium alloys have been used successfully in a variety of commercial systems due to their unusual combination of properties. These include low density, good corrosion resistance and excellent mechanical properties. However, they also have disadvantages which include a low resistance to fracture and fatigue under load. The addition of reinforcing particles improves these properties, but it may also upset the delicate balance which has been achieved over many years of fine tuning. This study addresses the areas of uncertainty concerning environmental sensitivity in a leading aluminium based silicon carbide particle reinforced metal matrix composite, under conditions of direct interest to the aerospace industry. The materials studied are 2XXX series aluminium alloys, AMC225, mechanically alloyed and powder blended conditions. The environments to which they have been subjected include immersion in 3.5% sodium chloride solution, from zero to 72 hours and a fog atmosphere of the same composition. It has been found that soaking the materials in this salt solution has a significant detrimental effect on fatigue performance, even after relatively short soaks of 8 hours. The LCF performance is independent of processing route in the T4 condition alloys. Lives to failure are dramatically reduced on the introduction of a saline environment, in which the process of corrosion pitting is implicated. Sensitivity to a salt fog environment is independent of waveform frequency. A "long crack" trend has been defined for DeltaK&gt;8MNm-3/2, which corresponds to the Paris regime, with Paris exponents of m=3.57 and c=3.49 x 10-11."</abstract><type>E-Thesis</type><journal/><journalNumber></journalNumber><paginationStart/><paginationEnd/><publisher/><placeOfPublication/><isbnPrint/><issnPrint/><issnElectronic/><keywords>Materials science.</keywords><publishedDay>31</publishedDay><publishedMonth>12</publishedMonth><publishedYear>2003</publishedYear><publishedDate>2003-12-31</publishedDate><doi/><url/><notes/><college>COLLEGE NANME</college><department>Engineering</department><CollegeCode>COLLEGE CODE</CollegeCode><institution>Swansea University</institution><degreelevel>Master of Philosophy</degreelevel><degreename>M.Phil</degreename><apcterm/><lastEdited>2018-08-16T14:39:02.9105634</lastEdited><Created>2018-08-02T16:24:29.2441846</Created><path><level id="1">Faculty of Science and Engineering</level><level id="2">School of Engineering and Applied Sciences - Uncategorised</level></path><authors><author><firstname>Julia Diane</firstname><surname>Shields</surname><orcid>NULL</orcid><order>1</order></author></authors><documents><document><filename>0042436-02082018162454.pdf</filename><originalFilename>10798144.pdf</originalFilename><uploaded>2018-08-02T16:24:54.2670000</uploaded><type>Output</type><contentLength>15829292</contentLength><contentType>application/pdf</contentType><version>E-Thesis</version><cronfaStatus>true</cronfaStatus><embargoDate>2018-08-02T16:24:54.2670000</embargoDate><copyrightCorrect>false</copyrightCorrect></document></documents><OutputDurs/></rfc1807>
spelling 2018-08-16T14:39:02.9105634 v2 42436 2018-08-02 Environmentally assisted fatique crack development in aluminium-based metal matrix composites. 0c8485dbbe0b3abe40e412889096e828 NULL Julia Diane Shields Julia Diane Shields true true 2018-08-02 "Aluminium alloys have been used successfully in a variety of commercial systems due to their unusual combination of properties. These include low density, good corrosion resistance and excellent mechanical properties. However, they also have disadvantages which include a low resistance to fracture and fatigue under load. The addition of reinforcing particles improves these properties, but it may also upset the delicate balance which has been achieved over many years of fine tuning. This study addresses the areas of uncertainty concerning environmental sensitivity in a leading aluminium based silicon carbide particle reinforced metal matrix composite, under conditions of direct interest to the aerospace industry. The materials studied are 2XXX series aluminium alloys, AMC225, mechanically alloyed and powder blended conditions. The environments to which they have been subjected include immersion in 3.5% sodium chloride solution, from zero to 72 hours and a fog atmosphere of the same composition. It has been found that soaking the materials in this salt solution has a significant detrimental effect on fatigue performance, even after relatively short soaks of 8 hours. The LCF performance is independent of processing route in the T4 condition alloys. Lives to failure are dramatically reduced on the introduction of a saline environment, in which the process of corrosion pitting is implicated. Sensitivity to a salt fog environment is independent of waveform frequency. A "long crack" trend has been defined for DeltaK>8MNm-3/2, which corresponds to the Paris regime, with Paris exponents of m=3.57 and c=3.49 x 10-11." E-Thesis Materials science. 31 12 2003 2003-12-31 COLLEGE NANME Engineering COLLEGE CODE Swansea University Master of Philosophy M.Phil 2018-08-16T14:39:02.9105634 2018-08-02T16:24:29.2441846 Faculty of Science and Engineering School of Engineering and Applied Sciences - Uncategorised Julia Diane Shields NULL 1 0042436-02082018162454.pdf 10798144.pdf 2018-08-02T16:24:54.2670000 Output 15829292 application/pdf E-Thesis true 2018-08-02T16:24:54.2670000 false
title Environmentally assisted fatique crack development in aluminium-based metal matrix composites.
spellingShingle Environmentally assisted fatique crack development in aluminium-based metal matrix composites.
Julia Diane Shields
title_short Environmentally assisted fatique crack development in aluminium-based metal matrix composites.
title_full Environmentally assisted fatique crack development in aluminium-based metal matrix composites.
title_fullStr Environmentally assisted fatique crack development in aluminium-based metal matrix composites.
title_full_unstemmed Environmentally assisted fatique crack development in aluminium-based metal matrix composites.
title_sort Environmentally assisted fatique crack development in aluminium-based metal matrix composites.
author_id_str_mv 0c8485dbbe0b3abe40e412889096e828
author_id_fullname_str_mv 0c8485dbbe0b3abe40e412889096e828_***_Julia Diane Shields
author Julia Diane Shields
author2 Julia Diane Shields
format E-Thesis
publishDate 2003
institution Swansea University
college_str Faculty of Science and Engineering
hierarchytype
hierarchy_top_id facultyofscienceandengineering
hierarchy_top_title Faculty of Science and Engineering
hierarchy_parent_id facultyofscienceandengineering
hierarchy_parent_title Faculty of Science and Engineering
department_str School of Engineering and Applied Sciences - Uncategorised{{{_:::_}}}Faculty of Science and Engineering{{{_:::_}}}School of Engineering and Applied Sciences - Uncategorised
document_store_str 1
active_str 0
description "Aluminium alloys have been used successfully in a variety of commercial systems due to their unusual combination of properties. These include low density, good corrosion resistance and excellent mechanical properties. However, they also have disadvantages which include a low resistance to fracture and fatigue under load. The addition of reinforcing particles improves these properties, but it may also upset the delicate balance which has been achieved over many years of fine tuning. This study addresses the areas of uncertainty concerning environmental sensitivity in a leading aluminium based silicon carbide particle reinforced metal matrix composite, under conditions of direct interest to the aerospace industry. The materials studied are 2XXX series aluminium alloys, AMC225, mechanically alloyed and powder blended conditions. The environments to which they have been subjected include immersion in 3.5% sodium chloride solution, from zero to 72 hours and a fog atmosphere of the same composition. It has been found that soaking the materials in this salt solution has a significant detrimental effect on fatigue performance, even after relatively short soaks of 8 hours. The LCF performance is independent of processing route in the T4 condition alloys. Lives to failure are dramatically reduced on the introduction of a saline environment, in which the process of corrosion pitting is implicated. Sensitivity to a salt fog environment is independent of waveform frequency. A "long crack" trend has been defined for DeltaK>8MNm-3/2, which corresponds to the Paris regime, with Paris exponents of m=3.57 and c=3.49 x 10-11."
published_date 2003-12-31T07:20:06Z
_version_ 1829539054275788800
score 11.05816

Similar Items