Micro Flash Welding of Super Duplex Stainless Steels

2007 ◽  
Vol 539-543 ◽  
pp. 3979-3984
Author(s):  
Toshio Kuroda ◽  
Kenji Ikeuchi ◽  
Takeshi Terajima
Keyword(s):  
Stainless Steel ◽  
Solid State ◽  
Duplex Stainless Steel ◽  
Stainless Steels ◽  
Welding Time ◽  
Butt Welding ◽  
Second Stage ◽  
Solid State Bonding ◽  
Super Duplex Stainless Steels ◽  
Flash Welding

Super duplex stainless steels were welded using new flash butt welding technology of temperature controlling system. The super duplex stainless steel (329J4L) and conventional duplex stainless steel (329J3L) were used. The samples were mounted in the dies using a Gleeble thermal simulator and flash but welding was made. The specimens were heated up to 1373K for 10sec, 20sec and 30sec. Flash butt welding has consisting of a two stage processes of a flash action and a contact resistance. First stage was a flash welding process and second stage was a solid state bonding process. The cross sectional microstructure of the weld bond region showed two types of a deposited fine particles region and a solid state bonding region. The grain growth was hardly observed in the weld region and the heat-affected zone. For further increasing joining efficiency of solid state bonding at the second stage, the welding time at 1373K was increased from 5 sec to 180sec. The bonding area increased with increasing welding time at 1373K and successfully welded for conventional duplex stainless steel.

Solid State Bonding of CuCrZr to Duplex Stainless Steel

2013 ◽  
Vol 302 ◽  
pp. 136-139 ◽  
Author(s):  
Ho Sung Lee ◽  
Jong Hoon Yoon ◽  
Joon Tae Yoo ◽  
Ji Ung Choi
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
High Temperature ◽  
Solid State ◽  
Duplex Stainless Steel ◽  
High Strength ◽  
Atomic Diffusion ◽  
Thermal And Mechanical Properties ◽  
Solid State Bonding ◽  
Duplex Steel

In the solid state bonding, joint are made by pressing surfaces together at high temperature so that a bond grows across the interface by atomic diffusion. In order to satisfy both requirements of thermal and mechanical properties of aerospace vehicle, conductive CuCrZr alloy was bonded to duplex steel with high strength. Solid state bonding was performed at 3 different pressure conditions and at temperatures of 850°C and 950°C. Microstructural and mechanical evaluation was performed to obtain the optimum joining condition.

Micro Flash Welding of Super Duplex Stainless Steel with Zr Metallic Glass Insert

2008 ◽  
Vol 580-582 ◽  
pp. 53-56
Author(s):  
Toshio Kuroda ◽  
Kenji Ikeuchi ◽  
Masahiro Shimada ◽  
Akihisa Inoue ◽  
Hisamichi Kimura
Keyword(s):  
Stainless Steel ◽  
Metallic Glass ◽  
Duplex Stainless Steel ◽  
Superplastic Deformation ◽  
Super Duplex Stainless Steel ◽  
Butt Welding ◽  
Metal Insert ◽  
Controlling System ◽  
Metallurgical Bonding ◽  
Flash Welding

Micro flash butt welding of super duplex stainless steel with Zr-based metallic glass insert was carried out using the temperature controlling system. Zr55Cu30Ni5Al10 of Zr-based metallic glass with thickness of 0.05mm and Zr metal with thickness of 0.1mm and 0.5 mm were used as the insert materials, in order to improve weldability. The specimens were mounted on the dies using a Gleeble thermal simulator, and then, flash butt welding was made. After welding, Zrbased metallic glass insert became much thinner than Zr metal insert. The super-cooled liquid in the interface protruded outside due to the superplastic deformation. The formation of the protrusion discharged the oxide films on the butting surfaces and contact surface; resulting in metallurgical bonding through the fresh surfaces. The Fe-Zr metallic compound for Zr-based metallic glass insert was hardly observed. The micro flash butt welding with metallic glass insert was successfully accomplished for super duplex stainless steel.

Corrosion Risk and Repassivation of Duplex Stainless Steel UNS S82551 in Treated Seawater Injection Service

CORROSION ◽  
10.5006/3697 ◽  
2021 ◽  
Author(s):  
Nicolas Larche ◽  
Perry Nice ◽  
Hisashi Amaya ◽  
Lucrezia Scoppio ◽  
Charles Leballeur ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Dissolved Oxygen ◽  
Duplex Stainless Steel ◽  
Oxygen Content ◽  
Alloy Steel ◽  
Stainless Steels ◽  
Crevice Corrosion ◽  
Low Alloy Steel ◽  
Corrosion Risk ◽  
Service Conditions

In seawater injection wells, the available well tubing materials are generally Low alloy steel, Glass Reinforced Epoxy lined low alloy steel or Corrosion Resistant Alloy’s (CRA) such as super duplex stainless steel. However, in treated seawater the corrosion risk can be controlled and lower grade alloys (low alloy steel) can be considered. But for long well lifetime designs (20 years plus), then low alloy steel tubing can be challenged. In this respect recent efforts have focused attention on better dissolved oxygen control which permits the investigation and on the possible use of more cost-effective materials such as the duplex stainless steels UNS S82551, and UNS S82541 (the latter is a higher strength version, but same PRENw). Full scale testing of tubes joined together with a proprietary premium threaded connection (PCPC couplings) was performed in controlled seawater loops simulating service conditions at 30°C. The flow rate and dissolved oxygen were controlled at 5 m/s and <20ppb, respectively. Weekly dissolved oxygen excursions corresponding to 24h at 100ppb followed by 1 hour at 300ppb were performed during the 5 months exposure. Corrosion results of UNS S82551/S82541 tubing were compared to UNS S31803 and UNS S39274. In parallel, laboratory exposures of creviced coupons for parametric study were performed in dissolved oxygen-controlled cells, allowing the measurement of electrochemical potentials as function of dissolved oxygen content and the related corrosion resistance. The results showed that dissolved oxygen content should be properly controlled below critical values to avoid crevice corrosion of the lesser alloyed duplex stainless steels. The ability of UNS S82541 to recover or re-passivate after prolonged exposures to high dissolved oxygen concentrations (DOC) was also determined with both the use of full sized pipe-coupling premium connection (PCPC) test cells, and electrochemical testing involving a Remote Crevice Assembly (RCA). The re-passivation potential was investigated after different active crevice corrosion durations. The results of the study allowed to precisely define the limits of use of UNS S82541 in treated seawater, i. e. the critical DOC conditions for corrosion initiation and for re-passivation of UNS S82541. For all tested conditions, the UNS S82551/S82541 showed a rather good ability to re-passivation when normal service conditions (i. e. low dissolved oxygen) are recovered.

Corrosion Resistance of Dissimilar GTA Welds of Pipeline Steel and Super Duplex Stainless Steels in Synthetic Brine

CORROSION ◽  
10.5006/3746 ◽  
2021 ◽  
Author(s):  
Víctor Vargas ◽  
Apolinar Albiter-Hernandez ◽  
Marco Dominguez Aguilar ◽  
Gerardo Altamirano-Guerrero ◽  
Cuahtemoc Maldonado
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Duplex Stainless Steel ◽  
Pipeline Steel ◽  
Localized Corrosion ◽  
Nickel Wire ◽  
Super Duplex Stainless Steel ◽  
Gas Tungsten Arc ◽  
Dissimilar Welds ◽  
Super Duplex Stainless Steels

The effect of weld passes and single V grove designs, on the corrosion resistance of dissimilar welds of a low alloy steel and a super-duplex stainless steel, was studied in synthetic brine. Welds were manufactured in argon by gas tungsten arc (GTA) technique and joined by a high nickel wire of super-duplex stainless steel. Samples of weld regions were characterized by composition scans, electrochemical measurements, micro-hardness and scanning electron microscopy. In X52/ER2594, a transition region (TR) of grain boundaries type II and a band of martensite were formed. The base metal of X52 underwent the highest corrosion rate and localized corrosion occurred in the heat affected zone. Interface ER2594/25Cr7Ni and 25Cr7Ni showed the presence of pitting near intermetallics.

Use of Duplex Stainless Steel in Economic Design of a Pressure Vessel

2006 ◽  
Vol 129 (1) ◽  
pp. 155-161 ◽  
Author(s):  
Milan Veljkovic ◽  
Jonas Gozzi
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Stainless Steels ◽  
Pressure Vessel ◽  
Design Procedure ◽  
High Strength Steels ◽  
High Strength ◽  
Pressure Vessels ◽  
Economic Design ◽  
European Standard

Pressure vessels have been used for a long time in various applications in oil, chemical, nuclear, and power industries. Although high-strength steels have been available in the last three decades, there are still some provisions in design codes that preclude a full exploitation of its properties. This was recognized by the European Equipment Industry and an initiative to improve economy and safe use of high-strength steels in the pressure vessel design was expressed in the evaluation report (Szusdziara, S., and McAllista, S., EPERC Report No. (97)005, Nov. 11, 1997). Duplex stainless steel (DSS) has a mixed structure which consists of ferrite and austenite stainless steels, with austenite between 40% and 60%. The current version of the European standard for unfired pressure vessels EN 13445:2002 contains an innovative design procedure based on Finite Element Analysis (FEA), called Design by Analysis-Direct Route (DBA-DR). According to EN 13445:2002 duplex stainless steels should be designed as a ferritic stainless steels. Such statement seems to penalize the DSS grades for the use in unfired pressure vessels (Bocquet, P., and Hukelmann, F., 2001, EPERC Bulletin, No. 5). The aim of this paper is to present an investigation performed by Luleå University of Technology within the ECOPRESS project (2000-2003) (http://www.ecopress.org), indicating possibilities towards economic design of pressure vessels made of the EN 1.4462, designation according to the European standard EN 10088-1 Stainless steels. The results show that FEA with von Mises yield criterion and isotropic hardening describe the material behaviour with a good agreement compared to tests and that 5% principal strain limit is too low and 12% is more appropriate.

Examination of the Orientation Relationships between the Main Phases of Duplex Stainless Steel by EBSD

2007 ◽  
Vol 537-538 ◽  
pp. 297-302
Author(s):  
Tibor Berecz ◽  
Péter János Szabó
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Stainless Steels ◽  
Electron Backscatter Diffraction ◽  
Duplex Stainless Steels ◽  
Alloying Elements ◽  
Orientation Relationships ◽  
Σ Phase ◽  
Electron Backscatter ◽  
Backscatter Diffraction

Duplex stainless steels are a famous group of the stainless steels. Duplex stainless steels consist of mainly austenitic and ferritic phases, which is resulted by high content of different alloying elements and low content of carbon. These alloying elements can effect a number of precipitations at high temperatures. The most important phase of these precipitation is the σ-phase, what cause rigidity and reduced resistance aganist the corrosion. Several orientation relationships have been determined between the austenitic, ferritic and σ-phase in duplex stainless steels. In this paper we tried to verify them by EBSD (electron backscatter diffraction).

Effect of Different Cooling Rate on HAZ Microstructure of 2205 Duplex Stainless Steels

2009 ◽  
Author(s):  
Qingren Xiong ◽  
Yaorong Feng ◽  
Wenzhen Zhao ◽  
Chunyong Huo ◽  
Chuan Liu ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Cooling Rate ◽  
Stainless Steels ◽  
Duplex Stainless Steels ◽  
Temperature Range ◽  
2205 Duplex Stainless Steel ◽  
Microstructure Transformation ◽  
Microstructure Morphology ◽  
Phase Proportion

The effects of cooling rate ω8/5 and ω12/8 on the simulated HAZ microstructure transformation in 2205 duplex stainless steel are studied in this paper. The results indicate that 1200°C ∼ 800°C is the temperature range in which the microstructure transits the most violently for 2205 steel, and is also the cooling interval, that affects the phase proportion and microstructure morphology the most distinctly. Accordingly, It is more efficient to use ω12/8 as the parameter to investigate the microstructure transformation of welding HAZ microstructure of this material. The cooling rate in this interval will affect the microstructure transformation of HAZ microstructure of 2205 steel remarkably.

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