Effect of microstructure on impact toughness of duplex and superduplex stainless steels

• Autorzy: Topolska S. , Łabanowski J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: of this paper is to study the effect of heat treatments and resulting changes in microstructure on mechanical properties, mainly impact toughness, of commercial 2205 duplex stainless steel and higher alloy superduplex 2507 grade. Design/methodology/approach: Both steels were submitted to ageing treatments in the temperature range of 500-900 °C with exposure time periods 6 minutes, 1 hour and 10 hours. Light microscope examinations, hardness measurements and impact toughness tests were performed in order to reveal microstructure and changes in mechanical properties. Findings: Obtained results confirm that high temperature service of duplex stainless steels should be avoided. Precipitations of secondary phases (mainly ó phase) strongly deteriorate mechanical properties of steels but some amounts of these phases could be acceptable in the microstructure depending upon the application of the steel. Research limitations/implications: Presence of secondary phases in duplex stainless steel microstructure can be very harmful for its corrosion resistance. This phenomenon is not considered in this study. Practical implications: The accidents during exploitation and errors in processing of duplex stainless steels can result in undesired temperature growth over 500°C. Such events brings question whether the steel can be still exploited or not. The aim of present study is to reveal the effect of thermal cycles on structural changes and mechanical properties of duplex stainless steel and establish the highest acceptable time-temperature conditions for safe operation of the steel. Originality/value: Information available in literature does not clearly indicate what amount of secondary phases existing in duplex stainless steel microstructure can be acceptable. The current study shows that duplex 2205 steel affected by thermal cycles and containing about 10% of sigma phase still exhibit acceptable mechanical properties.

Słowa kluczowe

EN

ductility; duplex stainless steel; heat treatment; impact toughness

PL

ciągliwość; stal nierdzewna duplex; obróbka cieplna; wytrzymałość uderzeniowa

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2009
• Tom: Vol. 36, nr 2
• Strony: 142--149
• Opis fizyczny: Bibliogr. 20 poz., rys., tabl.

Twórcy

autor

Topolska S.

autor

Łabanowski J.

• Division of Division of Constructional and Special Materials, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland,

Bibliografia

• [1] J. Charles, Composition and properties of duplex stainless steels, Welding in the World 36 (1995) 89-97.
• [2] J. Łabanowski, Duplex stainless steels - new material for chemical industry. Apparatus and Chemical Engineering 36/2 (1997) 3-10 (in Polish).
• [3] J. Frodigh, J. Nicholls, Mechanical properties of Sandvik duplex stainless steels, AB Sandvik Steel, 1994.
• [4] X. Wang, D. Dumortieir, Y. Riquier, Structural evolution of Zeron 100 duplex stainless steel between 550 and 1100°C, Proceedings of the Conference “Duplex stainless steels '91”, Beaune, 1991, 331-342.
• [5] L. Karlsson, L. Ryen, S. Pak, Precipitation of intermetallic phases in 22% duplex stainless weld metals, Welding Journal 1 (1995) 115-122.
• [6] J. Charles, The duplex stainless steels: materials to meet your needs, Proceedings of the Conference “Duplex stainless steels '91”, Beaune, 1991.
• [7] L. Karlsson, Intermetallic phase precipitation in duplex stainless steels and weld metals metallurgy, influence on properties and welding aspects, Welding in the World 43/5 (1999) 20-40.
• [8] Practical guidelines for the fabrication duplex stainless steels, International Molybdenum Association, 2001.
• [9] T. Otarola, S. Hollner, B. Bonnefois, M. Anglada, L. Coudreuse, A. Mateo, Embrittlement of superduplex stainless steel in the range of 550-700°C, Engineering Failure Analysis 12 (2005) 930-941.
• [10] J. Łabanowski, Effect of microstructure on mechanical properties of duplex stainless steel for marine applications, Marine Technology Transactions, Polish Academy of Sciences, Branch in Gdańsk 10 (1999) 213-226.
• [11] T. H. Chen, K. L. Weng, JR. Yang, The effect of high temperatures exposure on the microstructural stability and toughness property in a 2205 duplex stainless steel, Materials Science and Engineering A 338/1-2 (2002) 259-270.
• [12] V. Kuzucu, M. Ceylan, M. Aksoy, M. Kaplan, Investigation of the microstructures of iron based wrought Cr-Ni-Mo duplex alloy, Journal of Materials Processing Technology 69/1-3 (1997) 247-256.
• [13] M. Vasudevan, A. Bhaduri, Baldev Raj, K. Prasad Rao, Delta ferrite prediction in stainless steel welds using neural network analysis and comparison with other prediction methods, Journal of Materials Processing Technology 142/1 (2003) 20-28.
• [14] 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.
• [15] J. Łabanowski, Stress corrosion cracking susceptibility of dissimilar stainless steel welded joints, Journal of Achievements in Materials and Manufacturing Engineering 20 (2007) 255-258.
• [16] J. Łabanowski, Mechanical properties and corrosion resistance of dissimilar stainless steel welds, Archives of Materials Science and Engineering 28/1 (2007) 27-33.
• [17] L. A. Dobrzański, Z. Brytan , M. Actis Grande, M. Rosso, Properties of duplex stainless steels made by powder metallurgy, Archives of Materials Science and Engineering 28/4 (2007) 217-233.
• [18] G. Niewielski, K. Radwanski, D. Kuc, The impact of deformation on structural changes of the duplex steel, Journal of Achievements in Materials and Manufacturing Engineering 23/1 (2007) 31-34.
• [19] J. Nowacki, A. Łukojc, Structure and properties of the heat-affected zone of duplex steels welded joints, Journal of Materials Processing Technology 164-165 (2005) 1074-1081.
• [20] H. Sieurin, R. Sandstrom, Fracture toughness of welded duplex stainless steel, Engineering Failure Analysis 73 (2006) 377-390.