Analysis of the precipitation and growth processes in a high-temperature Fe-Ni alloy

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

Abstrakty

EN

Purpose: The influence of prolonged aging on the precipitation process of the intermetallic phases, carbide and boride in high-temperature Fe-Ni austenitic alloy has been studied. Taking advantage of the LSW theory, at attempt was undertaken to provide a quantitative description of the γ' phase 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 and mean distance between particles. In accordance with the LSW theory, linear dependencies of changes in mean diameter as a function of t1/3 were elaborated and the activation energy (E) of the γ' phase coagulation process was determined. Practical 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 and the distributions of temperatures 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 and using theory LSW to describe a growth and coagulation processes of particles γ' phase in high-temperature Fe-Ni alloy.

Słowa kluczowe

EN

metallic alloys; heat treatment; precipitation and coagulation; LSW theory

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2008
• Tom: Vol. 31, nr 2
• Strony: 226--232
• Opis fizyczny: Bibliogr. 17 poz,. wykr.

Twórcy

autor

Ducki K. J.

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

Bibliografia

• [1] S. Asgari, Structure and strain hardening of superalloy AEREX 350, Journal of Materials Processing Technology 118 (2001) 246-250.
• [2] H. S. Jeong, J. R. Cho, H. C. Park, Microstructure prediction of Nimonic 80A for large exhaust valve during hot closed dieforging, Journal of Materials Processing Technology 162-163 (2005) 504-511.
• [3] P. Jonsta, Z. Jonsta, J. Sojka, L. Cizek, A. Hernas, Structural characteristics of nickel super alloy INCONEL 713LC after heat treatment, Journal of Achievement in Materials and Manufacturing Engineering 21/2 (2007) 29-32.
• [4] M. Konter, M. Thumann, Materials and manufacturing of advanced industrial gas turbine components, Journal of Materials Processing Technology 117 (2001) 386-390.
• [5] K. J. Ducki, Precipitation and growth of intermetallic phase in a high-temperature Fe-Ni alloy, Journal of Achievements in Materials and Manufacturing Engineering 18 (2006) 87-90.
• [6] S. A. Sajjadi, S. M. Zebarjad, Study of fracture mechanisms of a Ni-Base superalloy at different temperatures, Journal of Achievements in Materials and Manufacturing Engineering 18 (2006) 227-230.
• [7] R. Shargi-Moshtaghin, S. Asgari, The influence of thermal exposure on the γ' precipitates characteristics and tensile behaviour of superalloy IN-738LC, Journal of Materials Processing Technology 147 (2004) 343-350.
• [8] J. M. Zhang, Z. Y. Gao, J. Y. Zhuang, Z. Y. Zhong, Grain growth model of IN718 during holding period after hot deformation, Journal of Materials Processing Technology 101 (2000) 25-30.
• [9] I. M. Lifshitz, V. V. Slyozow, The kinetics of precipitation from supersaturated solid solution, Journal of Physics and Chemistry of Solids 19 (1961) 35-50.
• [10] C. Wagner, Theory of transformation in sludge throw theresolution, Journal of Electrocemic 65 (1961) 581-591 (in German).
• [11] K. Kusabiraki, Y. Takasawa, T. Ooka, Precipitation and Growth of γ' and η Phases in 53Fe-26Ni-15Cr alloy, ISIJ International 35 (1995) 542-547.
• [12] A. Czyrska-Filemonowicz, B. Dubiel, K. Wiencek, Determination of the oxide particle density in ODS alloys means of transmission electron microscopy, Acta Stereologica 17/2 (1998) 225-236.
• [13] A. Wasilkowska, M. Bartsch, U. Messerschmidt, R. Herzog, A. Czyrska-Folemonowicz, Creep mechanisms of ferritic strengthened alloys, Journal of Materials Processing Technology 133 (2003) 218-224.
• [14] B. Dubiel, J. Wosik, H. J. Penkalla, A. Czyrska- Filemonowicz, Quantitative TEM microstructural analysis of Ni-based superalloy Waspaloy, Proceedings of the Stereology and Image Analysis in Materials Science, Kraków, 2000, 135-140.
• [15] J. H. Schröder, E. Arzt, Electron-Microscopic investigation of dispersion-strengthened superalloys, Praktische Metallography 25 (1988) 264-273.
• [16] F. B. Pickering, Some aspects of the precipitation of nicke-aluminium-titanium intermetallic compounds in ferrous materials, Proceedings of the International „Conference mThe metallurgical evolution of stainless steels”, London, 1979, 391-401.
• [17] K. J. Ducki, Analysis of the structure and precipitation strengthening in a creep resisting Fe-Ni alloy, Journal of Achievement in Materials and Manufacturing Engineering 21/2 (2007) 25-32.