Abstract
ZG0Cr26Ni5Mo3Cu3 Duplex Stainless Steel (DSS) was solution treated at 1,060 ºC for 3 h, followed by water cooling. Tempering treatments were conducted at 720, 750 and 780 ºC, respectively, for 16 h, followed by air cooling. The microstructures of ZG0Cr26Ni5Mo3Cu3 duplex stainless steel samples treated at different tempering temperatures were observed by scanning electron microscope (SEM) and energy dispersal spectroscopy (EDS), and the phase consitutions were analyzed using X-ray diffraction (XRD). The effects of the precipitation of sigma (σ) phase on the duplex phase percentage, hardness, impact toughness and corrosion resistance of the DSS were studied. Results showed that microstructures of ZG0Cr26Ni5Mo3Cu3 after solution treatment consists of ferrite (α) phase and austenite (γ) phase; after being tempered at different temperatures, σ phase appeared due to a eutectoid-type reaction of α→σ+γ2 during tempering treatment. It was observed that σ phase distributed along the grain boundary. The volume fraction of σ and γ phases increased with increasing tempering temperature in the range of 720 to 780 ºC, whereas the volume fraction of α phase showed the opposite trend. When the percentage of σ phase increased, the hardness of steel also increased. In the solution treated steel, hardness was measured to be only 244.0 HB, because σ phase did not appear. However, it increased to 391.8 HB when the DSS was tempered at 780 ºC because a great of deal of σ phase appeared. The impact toughness and corrosion resistance of DSS decreased when the percentage of σ phase increased.
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Yang S M, Chen Y C, Chen C H, et al. Microstructural Characterization of δ/γ/σ/γ2/X Phases in Silver-Doped 2205 Duplex Stainless Steel under 800 ºC Aging. Journal of Alloys and Compounds, 2015, 633: 48–53.
Lacerda J C D, Cândido L C and Godefroid L B. Effect of Volume Fraction of Phases and Precipitates on the Mechanical Behavior of UNS S31803 Duplex Stainless Steel. International Journal of Fatigue, 2015, 74(12): 81–87.
Park Y H, Lee Z H. The effect of nitrogen and heat treatment on the microstructure and tensile properties of 25Cr-7Ni-1.5Mo-3W-xN duplex stainless steel castings. Materials Science and Engineering A, 2001, 297(1-2): 78–84.
Geng S, Sun J, Guo L, et al. Evolution of Microstructure and Corrosion Behavior in 2205 Duplex Stainless Steel Gta-Welding Joint. Journal of Manufacturing Processes, 2015, 19:32–37.
Neessen F, Bandsma P and Smitweld L. Tankers -A composition in duplex stainless steels. Welding Innovation, 2001, 18: 3–8.
Ma M, Ding H, Misra R D K, et al. A Study on Precipitation Kinetics of Sigma Phase in a Hot-Rolled Super Duplex Stainless Steel During Isothermal Aging Based on the Johnson-Mehl-Avrami Model. Ironmaking & Steelmaking, 2016, 44(4): 311–318.
Nilsson J O. Super duplex stainless steels. Metal Science Journal, 2014, 8(8): 685–700.
Silva R, Baroni L F S, Silva M B R, et al. Effect of Thermal Aging at 475 ºC on the Properties of Lean Duplex Stainless Steel 2101. Materials Characterization, 2016, 114: 211–217.
Vijayalakshmi K, Muthupandi V and Jayachitra R. Influence of Heat Treatment on the Microstructure Ultrasonic Attenuation and Hardness of Saf 2205 Duplex Stainless Steel. Materials Science and Engineering A, 2011, 529(1): 447–451.
Zhang Z, Jing H, Xu L, et al. Investigation on Microstructure Evolution and Properties of Duplex Stainless Steel Joint Multi-Pass Welded by Using Different Methods, Materials & Design, 2016,109: 670–685.
Breda M, Pellizzari M and Frigo M. s-Phase in Lean Duplex Stainless Steel Sheets. Acta Metallurgica Sinica, 2015, 28(3): 331–337.
Tahaei A, Perez A F M, Merlin M, et al. Effect of the Addition of Nickel Powder and Post Weld Heat Treatment on the Metallurgical and Mechanical Properties of the Welded UNS S32304 Duplex Stainless Steel. Soldag lnsp, 2016, 21(2): 197–208.
Silva E D M, Leite J P, Fialho W M L, et al. Induced Magnetic Field Used to Detect the Sigma Phase of a 2205 Duplex Stainless Steel. Journal of Nondestructive Evaluation, 2016, 35(2): 1–10.
Santos D C D and Magnabosco R. Kinetic Study to Predict Sigma Phase Formation in Duplex Stainless Steels. Metallurgical and Materials Transactions A, 2016, 47(4): 1554–1565.
Fargas G, Mestra A and Mateo A. Effect of Sigma Phase on the Wear Behavior of a Super Duplex Stainless Steel. Wear, 2013, 303(1-2): 584–590.
Huallpa E A, Monlevade E F D, Campos M A, et al. Use of Magnetic Barkhausen Noise (MBN) to Follow up the Formation of Sigma Phase in Saf2205 (UNS S31803) Duplex Stainless Steel. Materials Research, 2016, 19(10): 8–16.
García C, Martín F, Blanco Y, et al. Effect of ageing heat treatments on the microstructure and intergranular corrosion of powder metallurgy duplex stainless steels. Corrosion Science, 2010, 52(11): 3725–3737.
Llorca-Isern N, López-Luque H, López-Jiménez I, et al. Identification of sigma and chi phases in duplex stainless steels. Materials Characterization, 2016, 112: 20–29.
Wang Y Q, Han J, Wu H C, et al. Effect of Sigma Phase Precipitation on the Mechanical and Wear Properties of Z3CN20.09M Cast Duplex Stainless Steel. Nuclear Engineering and Design, 2013, 259: 1–7.
Lee H W, Bae H S. Effect of Intermetallic Precipitation on the Properties of Multi Passed Duplex Stainless Steel Weldment. Korean Journal of Metals and Materials, 2014, 52: (8)631–636.
Beraha E, Shpigler B. Color metallography. Metals Park: American Society for Metals, 1977.
Maehara Y, Koike M, Fujino N, et al. Precipitation of s Phase in a 25Cr-7Ni-3Mo Duplex Phase Stainless Steel. ISIJ International, 1983, 23(3): 240–246.
Maehara Y, Fujino N, Kunitake T. Effects of Plastic Deformation and Thermal History on s Phase Precipitation in Duplex Phase Stainless Steels. ISIJ International, 1983, 23(3): 247–255.
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Male, born in 1964, Professor. His research interests mainly focus on wearand corrosion-resistant metal materials.
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Zhu, Zh., Zhang, Wd., Tu, Xh. et al. Effect of sigma phase precipitation on microstructure and properties of cast ZG0Cr26Ni5Mo3Cu3 duplex stainless steel under different heat treatments. China Foundry 15, 182–188 (2018). https://doi.org/10.1007/s41230-018-7226-z
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DOI: https://doi.org/10.1007/s41230-018-7226-z