Ultrasonic Characterization And Micro-Structural Studies On 2205 Duplex Stainless Steel In Thermal Variations
Bernice Victoria, Dr. Gene George, Kevin Ark Kumar
Index Terms: duplex steel, heat treatment, hygienic applications, microstructure, nondestructive, SAF, ultrasonic.
Abstract: Due to increasing concern on potential impact of materials on human health and environment, the materials used in hygienic applications should be durable, corrosion resistant, clean surface etc. Type 2205 duplex stainless steel is a preferred material for use in biomedical, pharmaceutical, nuclear pressure vessels, chemical tankers etc., it exhibits good mechanical strength and high resistance to corrosion. The strength, toughness, hardness of such materials are usually determined by destructive tests. However continuous destructive measurements are generally difficult to perform during the productive process, which creates a need for a fast and easy nondestructive method of material characterization. Microstructural changes in duplex stainless steel due to changes in annealing temperature are characterized by ultrasonic pulse –echo technique and optical microscopy. Type 2205 duplex stainless steel are heat treated at 1000 deg C, 1050 deg C, 1100 deg C, 1150 deg C and 1200 deg C for 15 min and water quenched. There is an appreciable change in the morphology of all the heat treated samples, and the ultrasonic velocity is dependent on both ferrite and austenite ratio and the grain size.
 M. Lewus, T. Newson, B Lee and D Dulieu, ―Review of metal release from ferritic, austenitic and duplex stainless steel grades exposed to potable water and related adverse environments‖, Proc of 4th European Stainless Steel Science and Market Congress, June 2002.
 IMA. ―The use of 2205 duplex stainless steel for pharmaceutical and biotechnology applications‖, published by International molybdenum association, London, ISBN 978-1-907470-25-7.
 Badija R, Bouabdallah M, Bacroix B, Kahloun C, Bettahar K, Kherrouba, ―Effect of solution treatment temperature on the precipitation kinetic of phase in 2205 duplex stainless steel welds.‖ Mater Sci Eng A, 2008;(1-2); 447-54
 Deng B Jiang Y, Gong J, Zhong C, Gao J, Li J. ―Critical pitting and repassivation temperatures for duplex stainless steel in chloride solution‖, Elecrochim Acta 2008;53(16);5220-5
 Tavares SSM, Terra Vf, Neto PL Matos DE, ―Corrosion resisance evaluation of the UNS S31803 duplex stainless steel aged at low temperatures (350-550) under DLEPR tests‖, J Mater Sci , 40, pp. 4025-4028, 2005.
 Jiang ZhL Chen XY, Huang H, Liu XY. ―Grain refinement of cr25Ni 5 Mo1.5 duplex stainless steel by heat treatment‖, Mater Sci Eng A, 2003; 363(1-2);263-7
 Duplex stainless steel datasheet, Outokumpu. http://www.outokumpu.com /sitecollectiondocuments/outokumpu-duplex-stainless-steel-data-sheet.pdf. accessed on May 23, 2015
 Chen TH Weng KL, Yang JR. ―The effect of high temperature exposure on the microstructural stability and toughness property in a 2205 duplex stainless
steel ―. Mater Sci Eng A, 2002.338 (1-2);259-70
 L.F Garfias-Mesias, J.M Sykes, ―Metastable pitting in 25 Cr duplex stainless steel‖, Corrosion Science, Volume 41, Issue 5, 1 May 1999, Pages 959-987, ISSN 0010-938X, http://dx.doi.org/10.1016/S0010-938X(98)00165-6.
 J. Stella, J. Cerezo, E. Rodríguez, ―Characterization of the sensitization degree in the AISI 304 stainless steel using spectral analysis and conventional ultrasonic techniques‖, NDT & E International, Volume 42, Issue 4, June 2009, Pages 267-274.
 Nishara Begum, V. Rajendran, T. Jayakumar, P. Palanichamy, N. Priyadharsini, S. Aravindan, Baldev Raj, ―On-line ultrasonic velocity measurements for characterisation of microstructural evaluation during thermal aging of β-quenched zircaloy-2‖, Materials Characterization, Volume 58, Issue 6, June 2007, Pages 563-570.
 Ashok kumar, Nidhi Gupta, Reeta gupta, Yudhisther kumar, ―Effect of coupling conditions on ultrasonic echo parameters‖, Ultrasonic, vol. 27 (2009) pp.70-79
 P. Palanichamy, A. Joseph, T. Jayakumar, Baldev Raj, ―Ultrasonic velocity measurements for estimation of grain size in austenitic stainless steel‖, NDT & E International, Volume 28, Issue 3, 1995, Pages 179-185.
 G. Radenkovic, Cvijovic, D. Mihajlovic, ―Effect of quenching temperature on micro-structure and properties of cast stainless steels‖, Acta Stereol. 13 (2), pp. 439-444, 1994.
 S.S.M. Tavares, J.M. Pardal, J.L. Guerreiro, A.M. Gomes, M.R. da Silva, ―Magnetic detection of sigma phase in duplex stainless steel UNS S31803‖