scholarly journals Duplex Steels Used in Building Structures and Their Resistance to Chloride Corrosion

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5666
Author(s):  
Mariusz Maslak ◽  
Marek Stankiewicz ◽  
Benedykt Slazak
Keyword(s):  
Corrosion Resistance ◽  
Resistance Testing ◽  
Building Structures ◽  
Corrosion Attack ◽  
Welded Structures ◽  
Technological Factors ◽  
Chloride Corrosion ◽  
Duplex Steel ◽  
Duplex Steels ◽  
Practical Recommendations

Welded structures made of duplex steels are used in building applications due to their resistance to local corrosion attack initiated by chlorides. In this paper, the material and technological factors determining the corrosion resistance are discussed in detail. Furthermore, recommendations are formulated that allow, in the opinion of the authors, to obtain a maximum corrosion resistance for welded joints. The practical aspects of corrosion resistance testing are also discussed, based on the results of qualification tests. This work is of a review character. The conclusions and practical recommendations are intended for contractors and investors of various types of structures made of the duplex steel. The recommendations concern the selection and use of duplex steels, including the issues of metallurgy, welding techniques, and corrosion protection.

Microstructure, Texture, Mechanical and Corrosion Performance of the Stainless Duplex Steel UNS S32205 Submitted to Warm Rolling

2018 ◽  
Vol 941 ◽  
pp. 118-123
Author(s):  
Dagoberto Brandão Santos ◽  
Raphael França Assumpção ◽  
Daniela Barçante Perasoli ◽  
Dalila Chaves Sicupira
Keyword(s):  
Tensile Strength ◽  
Stainless Steel ◽  
Corrosion Resistance ◽  
Duplex Stainless Steel ◽  
Warm Rolling ◽  
Optical Scanning ◽  
Transmission Electron ◽  
Duplex Steel ◽  
Hot Rolled ◽  
Chlorine Ion

The UNS S32205 duplex stainless steel was warm rolled at 600°C with 60 and 80% of thickness reduction. The microstructure was characterized by optical, scanning and transmission electron microscopy, X-ray diffractometry and EBSD. The corrosion resistance was evaluated by electrochemical behavior in the chlorine ion environment using potentiodynamic polarization measurements. The tensile strength reached 1185 MPa and 1328 MPa, after warm rolling with 60 and 80%, respectively. In steel as-supplied, hot rolled and annealed, the tensile strength was 774 MPa. Ferrite microtexture presented the α-fiber and the rotated cube component, while the austenite enhanced the brass, copper, and cube components to a lesser extent. The substructure was characterized by intense formation of tangles and forests of dislocations and discrete subgrains in the ferritic phase and by planar gliding of dislocations and formation of dense dislocations walls in the austenite. Despite the existence of a certain similarity among the values of pitting potentials obtained for all samples, the number of pits observed was higher in the as-received sample, followed by the samples with 60 and 80% reduction. These results draw attention to innovative routes in the industrial production of duplex stainless steel of this class, even considering ductility lost. Keywords: Warm rolling; Mechanical strength; Texture; Substructure; Corrosion resistance

Screening Tests of Inhibitors to Prevent Chloride Stress Corrosion★

CORROSION ◽  
1959 ◽  
Vol 15 (9) ◽  
pp. 18-22 ◽  
Author(s):  
J. H. PHILLIPS ◽  
W. J. SINGLEY
Keyword(s):  
Stress Corrosion ◽  
Sodium Sulfite ◽  
Screening Tests ◽  
Test Results ◽  
Corrosion Attack ◽  
Concentration Effects ◽  
Boiler Water ◽  
Chloride Corrosion ◽  
Alkaline Phosphate ◽  
Potential Inhibitors

Abstract Series of screening tests were run in tilting autoclaves to evaluate performance of selected, potential inhibitors in preventing chloride stress corrosion attack of Type 347 austenitic stainless steel in alkaline-phosphate boiler water containing 50 or 500 ppm chloride. From the test results, several inhibitors were tested further to evaluate concentration effects. Nitrate appeared to be a satisfactory inhibitor for oiler applications. Sodium sulfite also effectively prevented chloride corrosion cracking oy scavenging oxygen. 5.8.4

Effect of Ceria Additive on Microstructure and Properties of Laser-Cladded Bioceramic Coating

2010 ◽  
Vol 434-435 ◽  
pp. 586-589
Author(s):  
Min Zheng ◽  
Ding Fan ◽  
Jian Bin Zhang ◽  
Xiu Kun Li
Keyword(s):  
Corrosion Resistance ◽  
Rare Earth ◽  
Calcium Phosphate ◽  
Rare Earth Oxide ◽  
Resistance Testing ◽  
X Ray Diffraction ◽  
Microstructure And Properties ◽  
Transverse Flow Co2 Laser ◽  
Precursor Powders

The calcium phosphate bioceramic coating was fabricated on titanium alloy (Ti-6Al-4V) substrate by a 5kW continuous transverse flow CO2 laser. Due to the peculiar role of rare earth oxide in laser cladding, the effect of ceria additive on the microstructure and properties of laser-cladded bioceramic coating was investigated by means of scanning electron microscope (SEM), X-ray diffraction (XRD), microhardness and corrosion resistance testing. The results indicate that the appearance of rare earth oxide ceria in the precursor powders has an impact on the microstructure and properties of the laser-cladded bioceramic coating. Calcium phosphate bioceramic such as hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) are synthesized on the top surface of laser-cladded specimens. And the addition of rare earth oxide ceria in pre-placed powders has an influence on the formation of calcium phosphate bioceramic phases. Furthermore, it reveals that the laser-cladded bioceramic coating of ceria additive in pre-placed powders has more favorable microhardness and corrosion resistance compared with the coating without rare earth oxide.

scholarly journals Effect of Microstructure on Mechanical Properties and Corrosion Resistance of 2205 Duplex Stainless Steel

2015 ◽  
Vol 21 (4) ◽  
pp. 108-112 ◽  
Author(s):  
Jerzy Łabanowski ◽  
Aleksandra Świerczyńska ◽  
Santina Topolska
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Stress Corrosion ◽  
Structural Transformations ◽  
Shipbuilding Industry ◽  
Processing Technologies ◽  
Duplex Steel ◽  
Mechanical Properties And Corrosion ◽  
Chloride Environment ◽  
Low Strain Rate

Abstract This paper presents results of the research on impact of microstructure of austenitic-ferritic steel of duplex type on its mechanical properties and susceptibility to stress corrosion cracking. As showed, improper processing technologies more and more often used in shipbuilding industry for plates and other half-finished products made of duplex steel may cause significant lowering their properties, which frequently makes their replacing necessary. Results of the tests on stress corrosion under tension with low strain rate (SSRT) conducted in an inert and corrosion (boiling magnesium chloride) environment, are presented. It was proved that even minor structural transformations taking place in 500°C ageing temperature lower corrosion resistance of the steel. Structural transformations occurring in 700°C temperature to a smaller extent influence susceptibility to stress corrosion of the steel, however they cause drastic drop in its plasticity.

scholarly journals The Effect of Sn on the Corrosion Resistance of 25Cr-6Ni Duplex Steel

1984 ◽  
Vol 33 (1) ◽  
pp. 3-10
Author(s):  
Hachiro Imai ◽  
Ichiro Fukumoto
Keyword(s):  
Corrosion Resistance ◽  
Duplex Steel

scholarly journals Influence of temperature on corrosion resistance of austenitic stainless steel in cl− containing solutions

2019 ◽  
Vol 25 (25) ◽  
pp. 43-46
Author(s):  
Viera Zatkalíková ◽  
Lenka Markovičová
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Stainless Steels ◽  
External Factor ◽  
Corrosion Behaviour ◽  
Local Damage ◽  
Corrosion Attack ◽  
Temperature Changes ◽  
Influence Of Temperature ◽  
Influence Of Temperature On

Abstract Temperature is considered a complicated external factor of the susceptibility of stainless steels to the pitting. This paper deals with the corrosion behaviour of AISI 316Ti stainless steel in temperature range 22 - 80°C in aggressive chloride environments (3 and 5% FeCl3 solutions). The corrosion resistance of tested steel is evaluated on the base of results of exposure immersion tests and cyclic potentiodynamic tests. According to the obtained results the resistance of AISI 316Ti to the pitting is markedly affected by temperature changes in the range 22 – 80°C. Intensity of corrosion attack increases with the rise of Cl− concentration. Gentle changes of temperature and Cl− concentration cause significant differences in character of local damage. The appearance of pitted surfaces changes with the rise of the temperature (a density of pitting increases, a size of pits decreases). The strongest change in appearance is observed between 40 and 50ºC.

scholarly journals Coating Formation on Ti-6Al-4V Alloy by Micro Arc Oxidation in Molten Salt

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1611 ◽  
Author(s):  
Alexander Sobolev ◽  
Israel Wolicki ◽  
Alexey Kossenko ◽  
Michael Zinigrad ◽  
Konstantin Borodianskiy
Keyword(s):  
Corrosion Resistance ◽  
Protective Coatings ◽  
Oxide Coating ◽  
Resistance Testing ◽  
Morphological Examination ◽  
Protective Oxide ◽  
Coating Morphology ◽  
Micro Arc Oxidation ◽  
Coating Formation ◽  
Electrochemical Surface Treatment

Micro Arc Oxidation (MAO) is an electrochemical surface treatment process to produce oxide protective coatings on some metals. MAO is usually conducted in an aqueous electrolyte, which requires an intensive bath cooling and leads to the formation of a coating containing impurities that originate in the electrolyte. In the current work, we applied an alternative ceramic coating to the Ti-6Al-4V alloy using the MAO process in molten nitrate salt at a temperature of 280 °C. The obtained coating morphology, chemical and phase composition, and corrosion resistance were investigated and described. The obtained results showed that a coating of 2.5 µm was formed after 10 min of treatment, containing titanium oxide and titanium‒aluminum intermetallic phases. Morphological examination indicated that the coating is free of cracks and contains round, homogeneously distributed pores. Corrosion resistance testing indicated that the protective oxide coating on Ti alloy is 20 times more resistive than the untreated alloy.

scholarly journals New approach to development and manufacturing technologies of duplex steel

2019 ◽  
Vol 121 ◽  
pp. 04010
Author(s):  
Victor Orlov ◽  
Leonid Levkov ◽  
Vladimir Dub ◽  
Alan Balikoev ◽  
Dmitry Shurygin
Keyword(s):  
Oil And Gas ◽  
Sea Water ◽  
Average Distance ◽  
Production Equipment ◽  
Gas Production ◽  
Effective Control ◽  
Two Phase ◽  
Corrosion Properties ◽  
Duplex Steel ◽  
Duplex Steels

We conducted a brief review of current production and application of duplex and super duplex steels for manufacture of equipment exposed to the hazard of sulphide stress-corrosion cracking, sea water and other corrosive environment. The super duplex steel with enhanced corrosion-mechanical characteristics in comparison with the known steels of austenitic-ferritic class was developed. Based on the concepts of formation of a special structure of two-phase austenitic-ferritic steels in the process of crystallization, the possibilities of compositional, technological, thermal and special impact techniques are considered and advanced ways of controlling physical, chemical, structural homogeneity and properties of super duplex steels are developed. Electroslag remelting with the application of low-frequency alternating current provides effective control over the length of the two-phase area, the size of the primary dendrites of the austenitic and ferritic phases, the average distance between their axes, the parameters of the crystallizing cell, the development of liquation phenomena and the size of the growing non-metallic phases. Within framework of the proposed approach, the thermodynamic and kinetic conditions for the formation and growth of hardening phases are assessed, a new composition and a complex technology for the manufacture of corrosion-resistant super duplex steels for gas and oil production equipment has been developed. Thermodynamically stable, having sizes of 30-300 nm, niobium nitrides and carbonitrides are located inside the grains of the ferritic phase. At the same time, the sigma phase and chromium carbide precipitates at the intergrain boundaries are not observed. The results of the determination of mechanical and corrosion properties in accordance with the NACE TM 0177 standard (method A), tests of corrosion witness-samples in field conditions demonstrate the advantages and prospects of using new super duplex steel for the manufacture of oil and gas production equipment operating in an environment with high H2S content and CO2 under significant mechanical loads, without the risk of brittle fracture.

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