Quench ageing behaviour of duplex cast steel with nano-scale epsilon-Cu particles

• Autorzy: Dyja D. , Stradomski Z.
• Konferencja: 12th International Scientific Conference CAM3S'2006, 27-30th November 2006, Gliwice-Zakopane
• Języki publikacji: EN

Abstrakty

EN

Purpose: The aim of the study was to examine the effectiveness and usefulness of the quench ageing on the service properties of massive duplex cast steel. The mechanism of precipitation of a epsilon-Cu phase and its effect on the mechanical properties of the cast steel were investigated. Design/methodology/approach: The ferrite substructure was examined on a JOEL JEM HREM. The analysis of chemical composition of selected micro-regions was carried out using a scanning electron microscope. The verification of the metallographic examination results was done using the Thermo-Calc program. Findings: Quench ageing causes an increase in hardness and drop in impact resistance, which results from the formation of the epsilon-Cu phase. The ageing parameters have a substantial influence on the ferrite substructure and the degree of coherence, dispersion and amount of the epsilon-Cu phase. The ageing treatment at 480 degrees centigrade causes, in addition to the precipitation of the epsilon-Cu phase coherent with matrix, the formation of an alpha'-Cr phase and an alpha-Fe phase. Practical implications: Duplex cast steels are becoming an irreplaceable material in the elements of equipment exposed to the simultaneous action of corrosive and errosive environment. In the case of massive elements, such as pump (rotors and guide vanes) and pipeline elements etc., which are operated in corrosive environments of water suspensions of solids of different type and gradation, the effect of ageing will be much lower than in small laboratory specimens, which is associated with the presence of a large amount of the incoherent epsilon-Cu phase in the cast steel after the solution heat treatment. Originality/value: The lower limit of ageing temperature (480 degrees centigrade) coincide with the temperature of an undesirable spinodal decomposition of the ferrite, which is partially responsible for the slight increase in hardness and drop in plastic properties. This is the indication that the lower temperature of ageing duplex cast steels with copper should not be lower than 500 degrees centigrade.

Słowa kluczowe

EN

casting; heat treatment; quench ageing; epsilon-Cu precipitation

PL

odlewanie; obróbka cieplna; starzenie po przesycaniu; wydzielenia; miedź epsilon; faza epsilon

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 20, nr 1-2
• Strony: 435--438
• Opis fizyczny: Bibliogr. 15 poz., fot., tab.

Twórcy

autor

Dyja D.

autor

Stradomski Z.

• Institute of Materials Engineering, Faculty of Materials Processing Technology and Applied Physics, Częstochowa University of Technology, Al. Armii Krajowej 19, 42-200 Częstochowa, Poland,

Bibliografia

• [1] J. Kazior, T. Pieczonka, A. Molinari, Properties of AISI 316L, AISI 434L and duplex stainless steel, AMME'1999, 8 (1999), Gliwice, 289-292.
• [2] K. Kłyk-Spyra, M. Sozańska, Analysis of the fracture surface of duplex stainless steel after exposure to H2S, 8th European Congress on Stereology and Image Analysis, Zakopane, Poland, 2005, 246-252.
• [3] M.G. Alvarez, R.M. Carranza, The effect of temperature on the passive film properties and pitting behaviour of a Fe-Cr-Ni alloy, Corrosion Science 38 (1996) 909-925.
• [4] L.A. Dobrzański, Z. Brytan, M. Grande, M. Rosso, Corrosion resistance of sintered duplex stainless steel evaluated by electrochemical method, Journal of Achievements in Materials and Manufacturing Engineering 17 (2006) 317-320.
• [5] R.A. Perren, T.A. Suter, P.J. Uggowitzer, L. Weber, R. Magdowski, Corrosion resistance of super duplex stainless steels in chloride ion containing environments: investigations by means of a new microelectrochemical method part I, Corrosion Science 43 (2001) 707-726.
• [6] J. Nowacki, P. Rybicki, Influence of heat input on corrosion resistance of SAW welded duplex joints, Journal of Achievements in Materials and Manufacturing Engineering 17 (2006) 113-116.
• [7] Z. Pirowski, J. Wodnicki, A. Gwiżdż, The Cr26Ni5Mo3 cast steel structure optimization in order to improve erosive-corrosive properties, Acta Metallurgica Slovaka 8 (2002) 381-387.
• [8] Z. Stradomski, D. Dyja, S. Stachura, Technological problem in elaboration of massive casting from duplex cast steel, SSW Conference&Expo, Maastricht, 2005, 363-368.
• [9] P. Kangas, J. Nilsson, Influence of phase transformations on mechanical properties and corrosion properties in duplex stainless steels, SSW Conference&Expo, Maastricht, 2005, 278-283.
• [10] L.A. Dobrzański, M. Osojca Structure and properties of X2CrNiMoN22-5-3duplex steel, AMME'2003, 12 (2003), Gliwice-Zakopane, 263-266.
• [11] O. Smuk, H. Hanninen, J. Liimatainen, Mechanical and corrosion properties of P/M-HIP super duplex stainless steel after different industrial heat treatments as used for large components, Materials Science and Technology 20 (2004) 641-644.
• [12] J. Banaś, A.Mazurkiewicz, The effect of cooper on passivity and corrosion behavior of ferritic and ferritic-austenitic stainless steel, Materials Science and Engineering A277 (2000) 183-191.
• [13] M. Gajewski, Corrosive and erosive resistance precipitate strengthening cast steel, Foundry Rewiev 1 (2000) 16-21.
• [14] J. Banaś, J. Głownia, B. Kalandyk, B. Stypuła, Corrosion and passivity behavior of duplex stainless steel with nitrogen content, 3rd Kurt Schwabe Corrosion Symposium, Zakopane, Poland 2000, 235-240.
• [15] Z. Stradomski, S. Stachura, Austenitic-ferritic cast steel optimization for shipbuilding industry, Material Engineering 6 (2003) 377-379.