Grain refining of Cu and Ni-Ti shape memory alloys by ECAP process

• Autorzy: Greger M. , Kocich R. , Cizek L.
• Konferencja: 12th International Scientific Conference CAM3S'2006, 27-30th November 2006, Gliwice-Zakopane
• Języki publikacji: EN

Abstrakty

EN

Purpose: This paper was aimed at verification of functionality of the ECAP technology at extrusion of the copper and Ni-Ti alloys. Design/methodology/approach: Cross-section of original samples was 8 x 8 mm and their length was 32 mm. The samples of Cu were extruded at room temperature. For the samples of Ni-Ti alloys was used the two-stage pressing, when the samples were extruded at temperature of approx. T1 = 520 degrees centigrade and T2 = 420 degrees centigrade. In order to increase the concentration of deformation in volume of the sample, the samples were turned around their longitudinal axis by 90 degrees after individual passes and they were extruded again. Analysis of structure was made by using of light microscopy. Findings: deformation forces were measured during extrusion, resistance to deformation was calculated and deformation speed was approximately determined. After individual passes there is occured an accumulation of deformation strengthening (tau3 = 745 Mpa). Research limitations/implications: Microstructure depends on experimental conditions, particularly on number of passes and on rotation of the sample between individual passes. Orginality/value: SPD techniques as ECAP process can be used for non-ferrous metals like Ti, Cu. It was approved that elevated temperature provide a successfully conditions for the fine grained final materials obtaining.

Słowa kluczowe

EN

plastic forming; ECAP technology; Cu and Ni-Ti alloy; mechanical properties

PL

obróbka plastyczna; metoda ECAP; ECAP; stop miedzi, tytanu i niklu; właściwości mechaniczne

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 20, nr 1-2
• Strony: 247--250
• Opis fizyczny: Bibliogr. 15 poz., fot.

Twórcy

autor

Greger M.

autor

Kocich R.

autor

Cizek L.

• VSB - Technical University Ostrava, 17. listopadu 15, 708-33 Ostrava-Poruba, Czech Republic,

Bibliografia

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