Microstructure of AgSnBi powder consolidated in reciprocating extrusion process

• Autorzy: Richert M. W. , Richert J. , Hotloś A. , Perek-Nowak M. , Tokarski T. , Skiba J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The AgSnBi powder used for electrical contacts has been consolidated in the process of reciprocating extrusion (cyclic extrusion compression - CEC) in 2, 4, 8 and 16 CEC cycles at room temperature. It corresponds to the deformations: 2 CEC cycles - ϕ = 0.84, 4 CEC cycles - ϕ = 1.68, 8 CEC cycles - ϕ = 3.36 and 16 CEC cycles - ϕ = 6.72. The microstructure of consolidated powder has been characterized by optical microscopy (MO), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found characteristic granular microstructure with the oxides film at granular boundaries. Some voids and cracks were observed in consolidated samples, especially at higher magnifications. Inside the consolidated granules the nano-microstructure with nano - twins was found. Microhardness of AgSnBi after the consolidation by the CEC process achieved level of about 100-110 μHV. The microhardness of samples consolidated by CEC and then hydrostatically extruded increase of about 20 μHV units. Design/methodology/approach: The investigations of microstructure were performed by optical microscopy (MO) Olympus GX51, and scanning electron microscopy SU-70 with field emission gun thermally aided. The microhardness of consolidated samples was measured by Vickers method. Findings: The microstructures of consolidated AgSnBi powders were observed and analyzed. On the base of the microstructure and microhardness investigations the mechanisms of formation of bulk material from powder by severe plastic deformation (SPD) methods was discussed. Practical implications: The performed investigations contribute to the understanding of processes of deformation in the range of unconventional strains exerted by the SPD methods. The new way of consolidation of powders using to the production of electrical contacts was presented. Originality/value: It was assumed that AgSnBi powder consolidated by CEC and hydrostatic extrusion exhibited the nano-microstructure.

Słowa kluczowe

EN

consolidation; cyclic extrusion compression (CEC); hydrostatic extrusion; microstructure; powders; electrical contacts

PL

konsolidacja; cykliczne wyciskanie spęczające; wyciskanie hydrostatyczne; mikrostruktura; proszki; styki elektryczne

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2012
• Tom: Vol. 58, nr 2
• Strony: 120--124
• Opis fizyczny: Bibliogr. 8 poz.

Twórcy

autor

Richert M. W.

• AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Richert J.

• AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Hotloś A.

• AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Perek-Nowak M.

• AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Tokarski T.

• AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Skiba J.

• Institute of High Pressure Physics of the Polish Academy of Sciences, ul. Sokołowska 29/37, 01-142 Warszawa, Poland

Bibliografia

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