Precipitation and growth of intermetallic phase in a high-temperature Fe-Ni alloy

• Autorzy: Ducki K. J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The paper identifies the intermetallic phases, carbide and boride precipitating in the high-temperature Fe-Ni austenitic alloy during extended aging. Taking advantage of the LSW theory, at attempt was undertaken to provide a quantitative description of the γ’ phase [Ni3(Al,Ti)] particles growth as a function of temperature and aging time. Design/methodology/approach: The samples were subjected to a solution heat treatment at 980°C/2h/water, and then aged at 715, 750 and 780°C, with holding times 0.5-500 h. Structural investigations were conducted using transmission electron microscopy (TEM) and X-ray diffraction. Findings: Direct measurements on the electron micrographs allowed to calculate the structural parameters of the γ’ phase: mean diameter ( ), volume fraction (VV), and mean distance between particles (ld). In accordance with the LSW theory, linear dependencies of changes in as a function of t1/3 were elaborated for the analysed aging temperatures. From the slope of the Arrhenius straight line, the activation energy (E) of the γ’ phase coagulation process was determined, with its value estimated at 299kJ/mole. Research limitations/implications: The obtained data of γ’ phase particles growth as a function of temperature and aging time can be used to evaluate the degree of Fe-Ni alloys structure degradation during their operation at high temperatures. Originality/value: The paper touches upon the problem of the development of modern quantitative metallography methods with the use of thin foil technique.

Słowa kluczowe

EN

metallic alloy; heat treatment; precipitation; coagulation; LSW theory

PL

stop metali; obróbka cieplna; opad atmosferyczny; koagulacja

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 87--90
• Opis fizyczny: Bibliogr. 12 poz., rys., tab., wykr.

Twórcy

autor

Ducki K. J.

• Materials Science Department, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland

Bibliografia

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