miun.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Solidification studies of 3003 alloys with different Mn and Ti contents
Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.
Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences.ORCID iD: 0000-0002-3622-4247
2017 (English)In: Solidification processing 2017: proceedings of the 6th Decennial International Conference on Solidification Processing : 25-28 July 2017, Beaumont Estate, Old Windsor, UK / [ed] Fan, Zhongyun, bcast , 2017Conference paper, Published paper (Refereed)
Abstract [en]

Aluminum alloys of AA3003 are widely used in heat exchangers. This type of alloy mainly contains manganese as alloying element, but in recent developments there have been additions of both titanium and copper. The limits of Mn solubility in aluminum are influenced by these additions, which can cause the formation of large particles of an unwanted AlMnTi phase.

This project was initiated to investigate the effects of Mn contents in combination with Ti additions on the solidification and precipitation behavior using both Bridgman directional solidification and DTA equipment. The results show that coarse AlMnTi particles start forming when Mn contents are over 1.5 wt% in alloys with 0.14 wt% Ti and that the amount significantly increases with increasing Mn content from this level. Large particles were also found for Mn contents slightly below 1.4 wt%. If the Ti additions were on the level of 0.25 wt%. The DTA experiments show that AlMnTi phases grow in a limited temperature interval, and can reach a size of 150 microns. Such large sized particles are detrimental for the material in the ensuing rolling operation and must be avoided, and it is, therefore, important to accurately control the combinations of Mn and Ti contents.

Place, publisher, year, edition, pages
bcast , 2017.
Keywords [en]
Bridgman Technique, Differential Thermal Analysis, 3003 Alloy, Intermetallic Particles
National Category
Natural Sciences Materials Engineering
Identifiers
URN: urn:nbn:se:miun:diva-35020ISBN: 9781908549297 (print)OAI: oai:DiVA.org:miun-35020DiVA, id: diva2:1267544
Conference
6th Decennial international conference , 25-28 July 2017, old Windsor, UK
Available from: 2018-12-03 Created: 2018-12-03 Last updated: 2019-04-04Bibliographically approved
In thesis
1. Problems in the Aluminium DC Casting Process Associated with Melt Treatment Operations
Open this publication in new window or tab >>Problems in the Aluminium DC Casting Process Associated with Melt Treatment Operations
2019 (English)Doctoral thesis, comprehensive summary (Other academic) [Artistic work]
Abstract [en]

The quality of DC cast Al alloys is highly dependent on melt batch composition and impurity level in the molten alloy. The chemical composition and cleanliness of a melt is controlled through the melt treatment operations, carried out while the melt is still in the furnace before casting starts. The present work has studied some of these operations and associated problems such as slow dissolution of alloying elements, non-reproducibility in chemical composition analysis and inclusions.

 The results of the dissolution of the alloy elements Mn and Fe showed different behaviors.  For Mn three intermediate phases were involved, all of which exhibited a smooth interface between Mn and the liquid. These three phases were identified as the γ2, Al11Mn4, and µ phases, which grow slowly towards the dissolving Mn particles. The results from the Fe dissolution revealed that only one phase dominates the process, Al5Fe2, which penetrates the Fe particles with an irregular interface.

The interaction between Mn and Ti additions to AA3003 alloys and consequences for the solidification and precipitation behavior was investigated. The study could map the limits for formation of an earlier unknown AlMnTi phase, which formed large particles, detrimental for subsequent rolling operations.

Different sampling procedures for chemical composition analysis were studied, and a novel approach was proposed. A mould with an insulated periphery provided one-dimensional solidification, which gave compositions close to nominal.

 Inclusion distributions along as-cast billets were studied as a function of different holding times, and thus different grades of sedimentation. Holding times longer than 30 minutes did not show any improvements.  It was also shown that if melt remaining in the furnace at end of casting is less than about 3000 kg, the sedimented inclusions are stirred into the bulk again, and can enter into the end of the billet.

The impact on hot tearing susceptibility of different Cu and Fe contents for AA3000 alloys was studied. Cu contents in a range from 0.3 to 1.2 wt%  significantly increase the hot tearing tendency, which was attributed to bad feeding at end of solidification. Decreasing of the Fe content below 0.2 wt%, gives a strong cracking tendency, owing to decreased precipitations of the Al6(Mn,Fe) phase, which contributes to early bridging and thus reinforcement between grains.

Place, publisher, year, edition, pages
Sundsvall: Mid Sweden University, 2019. p. 67
Series
Mid Sweden University doctoral thesis, ISSN 1652-893X ; 294
National Category
Materials Engineering
Identifiers
urn:nbn:se:miun:diva-35937 (URN)978-91-88527-89-9 (ISBN)
Public defence
2019-04-25, M102, Holmgatan 10, Sundsvall, 13:00 (English)
Opponent
Supervisors
Note

Vid tidpunkten för disputationen var följande delarbeten opublicerade: delarbete 6 (inskickat).

At the time of the doctoral defence the following papers were unpublished: paper 6 (submitted).

Available from: 2019-04-04 Created: 2019-04-03 Last updated: 2019-04-04Bibliographically approved

Open Access in DiVA

No full text in DiVA

Authority records BETA

Razaz, GhadirCarlberg, Torbjörn

Search in DiVA

By author/editor
Razaz, GhadirCarlberg, Torbjörn
By organisation
Department of Natural Sciences
Natural SciencesMaterials Engineering

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 60 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf