Structure characteristics of intermetallic NiAlZr based compound

• Autorzy: Malcharcziková J. , Kursa M. , Pohludka M.
• Konferencja: Międzynarodowe Sympozjum Metody oceny struktury oraz własności materiałów i wyrobów (XXV ; 12-14.10.2010 ; Turawa, Polska
• Języki publikacji: EN

Abstrakty

EN

Observations were made in orientated state of inter-metallic Ni3Al based compound alloyed by zirconium. Zirconium in the form of wire or plasma melted foundry alloy Ni-Zr were used for preparation of the samples. The samples were cast by induction vacuum casting into the shape of cylinders. These castings were then directionally solidified in corundum tubes with the specified apex angle in a two-zone crystallisation furnace. Used rate of directional solidification was 50 mm/h. Cross sections and longitudinal sections of individual samples were used for determination of porosity, micro-hardness and for evaluation of character of created structures. It was established that the basic matrix contained formations of Ni3Al and elongated formations of Ni5Al3. Inter-dendritic regions contain eutectics with lamellar structure, which is formed by the Ni3Al phase and by the Zr-rich phase. Microhardness in the samples was determined in detail on the surface of the scratch pattern in polished state in accordance with precisely defined procedure, both in longitudinal and cross section. The scratch patterns were afterwards slightly etched in order to determine microhardness in individual phases and on grain boundaries. Microhardness was measured on microhardness tester FM-100 with use of the measuring unit "automatic microhardness testing system FM-ARS". It is very interesting that no big differences were found between the values of microhardness in the basic phase of Ni3Al rich in zirconium and grain boundaries, where this value varied approx. within the interval from 360š40 HV 0.05. Only eutectics formed by the Ni3Al phase and by the Zr-rich phase showed an increased microhardness. Evaluation of structure has been further completed with determination of porosity. Porosity in these samples was not too high and its value is of the order of hundreths of percent.

Słowa kluczowe

EN

component; NiAlZr; alloy; Zr; zirconium

PL

NiAlZr; komponent; stop; Zr

• Wydawca: Oficyna Wydawnicza Politechniki Opolskiej
• Czasopismo: Zeszyty Naukowe. Mechanika / Politechnika Opolska
• Rocznik: 2010
• Tom: z. 97
• Strony: 19--19
• Opis fizyczny: Bibliogr. 2 poz., rys., tab.

Twórcy

autor

Malcharcziková J.

autor

Kursa M.

autor

Pohludka M.

• VŠB -Technical University of Ostrava, Ostrava, Czech Republic

Bibliografia

• [1] WESTBROOK, J.H., FLEISCHER, R.L. et al. Intermetallic Compounds. Principles and Practice. Volume 2-Practice. New York, 1995.
• [2] DEEVI, S.C., SIKKA, V.K. Nickel and iron aluminides: an overview on properties, processing and applications. Intermetallics. 1996, vol. 4, p. 357-375.