Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • 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
Kontrollerad gjutprocess för renare stål
Jönköping University, School of Engineering, JTH, Mechanical Engineering.
Jönköping University, School of Engineering, JTH, Mechanical Engineering.
2014 (Swedish)Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesisAlternative title
Controlled casting process for cleaner steel (English)
Abstract [en]

In a multi-year project at Swerea Swecast AB studies on influence of dissolved gas on inclusions have been made. The knowledge about these parameters could be used to increase the quality of the final steel casting. The purpose of this thesis was to closer examine the impact of the oxygen level on inclusions.

The questions asked were:

 What was the amount of inclusions at different levels of oxygen?

 What was the size of these inclusions at different levels of oxygen?

 What does the inclusions consist of at different levels of oxygen?

This was studied by measuring and sampling, sample preparation and microscopic analysis using an optical microscope and a scanning electron microscope (SEM). Measurements and sampling was performed at Smålands Stålgjuteri AB in Eksjö and at Swerea Swecast AB in Jönköping. At Smålands Stålgjuteri AB the measurements were performed in production while at Swerea Swecast AB the measurements were made in a way that the oxygen levels were provoked.

The sample preparations were made at Swerea Swecast AB’s workshop and lab. Scanning electron microscopy (SEM) and light optic microscopy was used for the analysis. The data from these analyses were processed and charts and tables were prepared.

The results from the light microscopy shows a difference in microstructure between the two samplings. The charts and tables that were obtained indicated that the number of inclusions correlated with the oxygen level. However, only to a certain extent because other parameters such as time and amount of deoxidizer have a greater effect. The size of the inclusions decreased with decreased oxygen level during deoxidation. As mentioned in the pre-study, oxides are the most common type of inclusions in steel. This was also the case in the current study.

The results showed that the oxygen level can be used as an indicator of the necessary addition of deoxidiser.

Abstract [sv]

I ett flerårigt projekt på Swerea Swecast AB har undersökningar kring gasers inverkan på mängden inneslutningar i gjutstål genomförts. Kunskap kring hur parametrarna ser ut skulle användas för att höja kvaliteten på gjutgods. Syftet med det här arbetet var att noggrannare undersöka den fria syrehaltens påverkan på inneslutningar.

Frågeställningarna var:

 Hur stort antal inneslutningar fanns vid olika syrehalter?

 Hur stora var dessa inneslutningar vid olika syrehalter?

 Vad innehöll dessa inneslutningar vid olika syrehalter?

Detta undersöktes genom mätning och provtagning, provberedning och analys. Mätning och provtagning utfördes på Smålands Stålgjuteri AB i Eksjö och på Swerea Swecast AB i Jönköping. Vid Smålands Stålgjuteri AB utfördes mätningar under ordinarie produktion medan mätningarna på Swerea Swecast AB gjordes så att olika syrehalter provocerades fram.

Provberedningen och analysen gjordes i Swerea Swecast ABs verkstad och labb. Analysen gjordes med hjälp av svepelektronmikroskop (SEM) och ljusmikroskop. Data från dessa analyser bearbetades i Excel och diagram samt tabeller togs fram.

Resultatet från ljusmikroskopbilderna visar en skillnad i mikrostrukturer mellan de två gjutförsöken. Ur diagram och tabeller kan utläsas att antalet inneslutningar korrelerar med syrehalten. Dock bara till viss del eftersom andra parametrar såsom tid och mängd desoxidationsmedel har större påverkan. Storleken på inneslutningarna minskade tillsammans med syrehalten vid desoxidation. Vid en överdriven desoxidation kunde inneslutningar ansamlas i korngränserna vilket kraftigt försämrar de mekaniska egenskaperna. I förundersökningen nämndes att oxider var de vanligaste inneslutningarna i stål. Så var fallet även här.

Resultatet visar tydligt att syrehalten kan användas som indikator för hur stor tillsats av desoxidationsmedel som behövs.

Place, publisher, year, edition, pages
2014. , 63 p.
Keyword [en]
Steel, Casting, Inclusions, Oxygen level
Keyword [sv]
Stål, Gjutning, Inneslutningar, Syrehalt
National Category
Mechanical Engineering
Identifiers
URN: urn:nbn:se:hj:diva-24063OAI: oai:DiVA.org:hj-24063DiVA: diva2:723712
External cooperation
Swerea swecast AB
Subject / course
JTH, Mechanical Engineering
Supervisors
Examiners
Available from: 2014-06-16 Created: 2014-06-11 Last updated: 2014-06-16Bibliographically approved

Open Access in DiVA

Kontrollerad gjutprocess för renare stål(3897 kB)359 downloads
File information
File name FULLTEXT01.pdfFile size 3897 kBChecksum SHA-512
fa1b2965e841e8d694827cbd0b77a768bfb879ed217ae25dc516b1ba6b7a20ac1cdf8d5f63b27749513f06719d156af6c0e1f013b4ad9a6232059ea0b31458bc
Type fulltextMimetype application/pdf

By organisation
JTH, Mechanical Engineering
Mechanical Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 359 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 484 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • 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