The phase transformations during continuous cooling of Ti6Al7Nb alloy from the two-phase α+β range

• Autorzy: Dąbrowski R.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The phase transformations during continuous cooling from the two-phase α+β range in Ti6Al7Nb alloy has been determined. Design/methodology/approach: The phase transformations during continuous cooling of investigated alloy was elaborated using an L78 R.I.T.A dilatometer of the German Linseis Company. The microstructure of investigated alloy cooled from the two-phase α+β range was examinated by a light microscope Axiovert 200MAT. The measurements of hardness were performed with the Vickers HPO 250 apparatus. Findings: The relationship between cooling rate and microstructure morphology, hardness as well as dilatation effects has been determined. Research limitations/implications: The results will be used for the interpretation of phase transformations occurring at continuous cooling and at tempering from as-quenched state of the investigated alloy. Currently, the investigations of the kinetics phase transformation at continuous heating from as-quenched state will help to performed the Continuous-Heating-Transformation diagrams (CHT). These diagrams show the possibility of the regulation of the progress of successive (intermediate) transformations at tempering and thus influence the final alloy properties, including their hardness and fracture toughness. It is expected that the determination of final mechanical properties by means of regulating the progress of successive transformations occurring during heating from the as-quenched state is possible also in the Ti6Al7Nb alloy. Practical implications: The obtained results will be applied for the optimization of the heat treatment technology and for achieving the required mechanical properties of the Ti6Al7Nb alloy. Originality/value: The obtained results, supported in the future by additional cooling curves, will be used for the development of the original, full CCT diagram of the Ti6Al7Nb alloy cooled continuously from the two-phase α+β range.

Słowa kluczowe

EN

metallic alloys; titanium alloy; phase transformation; microstructure; dilatometric analysis

PL

stopy metali; stop tytanu; przemiana fazowa; mikrostruktura; analiza dylatometryczna

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2013
• Tom: Vol. 59, nr 1
• Strony: 7--12
• Opis fizyczny: Bibliogr. 22 poz., rys., tab.

Twórcy

autor

Dąbrowski R.

• Faculty of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, Al. A. Mickiewicza 30, 30-059 Kraków, Poland

Bibliografia

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