Friction stir modification of GTA 7075-T6 Al alloy weld joints: EBSD study and microstructural evolutions

• Autorzy: Shamanian M. , Mostaan H. , Safari M. , Szpunar J. A.

Identyfikatory

DOI

10.1016/j.acme.2017.01.002

• Języki publikacji: EN

Abstrakty

EN

As known, mechanical properties of gas tungsten arc welded 7075 Al alloys are not desirable and some techniques should be utilized in order to refine the microstructure and hence to improve the mechanical properties of weld joints. In this research work, the microstructure of gas tungsten arc welded 7075 Al alloy was modified by friction stir processing. Evaluation of the tensile strength of the welded joints showed that the tensile strength of the welded joint (228 MPa) increases up to 320 MPa after friction stir processing. In addition, electron backscattered diffractometry (EBSD) was used in order to study the microstructure and grain boundary character evolutions during arc welding and friction stir processing. It was revealed that as-cast dendritic microstructure of gas tungsten arc welded joint completely disappears during friction stir processing and very fine equiaxed grains are formed in welded joints. Analysis of EBSD data showed that friction stir processing of gas tungsten arc welded joints leads to increase of specific boundaries from 0.7% up to 7.8%. In addition, fraction of high angle boundaries increases after friction stir processing which is resulted from dynamic recrystallization occurring during friction stir processing.

Słowa kluczowe

EN

friction stir modification; gas tungsten arc welding; 7075 Al alloy; EBSD analysis; microstructure

PL

mikrostruktura; tarcie; spawanie

• Wydawca: Springer ; Wrocław University of Science and Technology
• Czasopismo: Archives of Civil and Mechanical Engineering
• Rocznik: 2017
• Tom: Vol. 17, no. 3
• Strony: 574--585
• Opis fizyczny: Bibliogr. 22 poz., rys., tab., wykr.

Twórcy

autor

Shamanian M.

• Department of Materials Engineering, Isfahan University of Technology, 84156-83111, Isfahan, Iran

autor

Mostaan H.

• Faculty of Engineering, Department of Materials and Metallurgical Engineering, Arak University, Arak 38156-8-8349, Iran

autor

Safari M.

• Department of Mechanical Engineering, Arak University of Technology, Arak, Iran

autor

Szpunar J. A.

• Department of Mechanical Engineering, University of Saskatchewan, Saskatoon, SK S7 N 5A9, Canada

Bibliografia

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Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017)