A quality problem in seam welds in aluminum extrusion

• Autorzy: Bingöl S. , Keskin M. S.
• Języki publikacji: EN

Abstrakty

EN

Purpose: Seam welds occur during the hollow profile extrusion; the billet's material is divided into separate metal streams by the bridges of the die which support a mandrel, and then these metal streams are welded in welding chamber behind the bridges. When the desired conditions have not been provided, the required quality in seam welds may not occur. One of the possible reasons for this situation is a poor metal feed. In this study, an insufficient pressure problem occurring in seam welds on an aluminum extrusion profile section is investigated. Design/methodology/approach: The study was realized on a hollow extrusion profile type which has seam weld zones. The experimental profile was produced by a real extrusion press which has a capacity of 1460 tones. Findings: The poor metal feed occurring on specimen is shown by microstructural pictures. Microstructure of the main region has a homogenous appearance. In the microstructure, containing seam weld region, only a slight change was observed in seam weld region. However, there was no significant change in near of seam weld regions. This points out that there has been no metallurgical problem. Therefore, the problem is an insufficient pressure problem and this caused poor metal feeding. In the other hand, micro hardness tests are realized on seam weld region, main region and defective region's surround of specimen's section. After the micro hardness tests important differences are shown among these regions' strength. Hardness values of seam weld region were lower than the main material's hardness values, but higher than the defective region's. Practical implications: In application, seam welds occur on hollow profiles produced by aluminum extrusion. Originality/value: As a result, this study shows a quality problem in seam welds in aluminum extrusion.

Słowa kluczowe

EN

metallic alloys; seam weld; aluminum; extrusion; porthole die; welding chamber

PL

stopy metaliczne; zgrzeina liniowa; aluminium; wyciskanie; spawanie komory

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2007
• Tom: Vol. 28, nr 7
• Strony: 397--400
• Opis fizyczny: Bibliogr. 16 poz., il., wykr.

Twórcy

autor

Bingöl S.

autor

Keskin M. S.

• Mechanical Engineering Department, Dicle University, 21280 Diyarbakir, Turkey,

Bibliografia

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