Analysis of the influence of dies geometry on the process extrusion force and properties of the extrudate obtained in the process of cold extrusion of 7075 aluminum alloy by the KOBO method

• Autorzy: Zwolak, Marek , Śliwa, Romana
• Języki publikacji: EN

Abstrakty

EN

The KOBO extrusion process is an unconventional method of extrusion based on the phenomenon of superplasticity as an effect of a special state caused by the oscillatory motion of the die at a certain angle a certain frequency. It significantly lowers the extrusion force and makes it possible to extrude lightweight metals and alloys (e.g. aluminum and magnesium alloys) in cold extrusion with high extrusion ratios compared to conventional hot extrusion. This work studies the influence of the tool (die) geometry on process realization parameters and the properties of the extrudate. Experimental studies of cold KOBO extrusion were performed using dies with different face portion geometry. The obtained extrudate obtained from EN-AW 7075 aluminum billets was examined for mechanical properties and macro/microstructure, showing that, with adequate modifications to the tool face part geometry, it is possible to lower the extrusion force and obtain extrudate with desired properties.

Słowa kluczowe

EN

aluminum extrusion; KOBO method; 7075 aluminum; bulk forming

• Czasopismo: Materials Science Poland
• Rocznik: 2024
• Tom: Vol. 42, No. 1
• Strony: 92--106
• Opis fizyczny: Bibliogr. 20 poz., rys., tab.

Twórcy

autor

Zwolak, Marek

• Department of Materials Forming and Processing, The Faculty of Mechanical Engineering and Aeronautics, Rzeszów University of Technology,

autor

Śliwa, Romana

• Department of Materials Forming and Processing, The Faculty of Mechanical Engineering and Aeronautics, Rzeszów University of Technology

Bibliografia

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Identyfikatory

DOI

10.2478/msp-2024-0008