La corrosion par piqûres d'aciers inoxydables austéno-ferritiques dans l'eau de mer synthétique

1996 ◽  
Vol 84 ◽  
pp. 23-30
Author(s):  
I. Trigui ◽  
H. Sidhom ◽  
C. Braham ◽  
J. Lédion
Keyword(s):  
Corrosion Resistance ◽  
Pitting Corrosion ◽  
Sea Water ◽  
Phase Behaviour ◽  
High Nitrogen ◽  
Electrochemical Tests ◽  
Analysis Techniques ◽  
Pitting Corrosion Resistance ◽  
Nitrogen Contents ◽  
Image Analysis Techniques

Duplex stainless steels crevice and pitting corrosion resistance in synthetic sea water is studied. Conventional electrochemical tests and image analysis techniques are used. Three commercial steels are examined. The forged material has the best behaviour, whereas cast materials, in spite of their high nitrogen contents, have a lower corrosion resistance. Micrographic studies show a good correlation between pittings distribution and inclusions distribution and reveal that gamma phase behaviour is more affected by inclusions. The metallurgic purity of products seems to be the most important parameter in this type of corrosion. Consequently, the PREN index is questionable in pitting corrosion grading of these steels because it does not take into acount the inclusions effect.

NIROSTA 4429

Alloy Digest ◽  
2000 ◽  
Vol 49 (5) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Pitting Corrosion ◽  
Intergranular Corrosion ◽  
Heat Treating ◽  
Low Carbon ◽  
High Nitrogen ◽  
Temperature Performance ◽  
Pitting Corrosion Resistance

Abstract Nirosta 4429 is a low-carbon, high-nitrogen version of type 316 stainless steel. The low carbon imparts intergranular corrosion resistance while the nitrogen imparts both higher strength and some increased pitting corrosion resistance. It is recommended for use as welded parts that need not or cannot be annealed after welding. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-787. Producer or source: ThyssenKrupp Nirosta.

COMPARISON ON PITTING CORROSION RESISTANCE OF NICKEL AND CHROMIUM IN TYPICAL SEA WATER RESISTANCE STEELS

2010 ◽  
Vol 46 (6) ◽  
pp. 748-754 ◽  
Author(s):  
Guoliang CAO ◽  
Guoming LI ◽  
Shan CHEN ◽  
Wanshun CHANG ◽  
Xuequn CHEN
Keyword(s):  
Corrosion Resistance ◽  
Pitting Corrosion ◽  
Water Resistance ◽  
Sea Water ◽  
Pitting Corrosion Resistance

Influences of Aging Precipitation on Corrosion Resistance of 18Cr-18Mn-2Mo-0.77N HNS

2009 ◽  
Vol 79-82 ◽  
pp. 1013-1016 ◽  
Author(s):  
Zu Rui Zhang ◽  
Hua Bing Li ◽  
Zhou Hua Jiang ◽  
Zhen Li ◽  
Bao Yu Xu
Keyword(s):  
Corrosion Resistance ◽  
Pitting Corrosion ◽  
Volume Fraction ◽  
Aging Treatment ◽  
High Nitrogen ◽  
Aging Precipitation ◽  
Pitting Corrosion Resistance ◽  
Nitrogen Steel ◽  
The Matrix ◽  
Nose Temperature

Influences of aging precipitation of Cr2N and Chi (χ) phases on the resistance to pitting corrosion and intergranular corrosion of 18Cr-18Mn-2Mo-0.77N high nitrogen steel (HNS) as a type of fundamental and structural materials were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) pattern and electrochemical methods. Intergranular, cellular Cr2N and χ phases precipitate gradually along grain boundaries and inward grains. The volume fraction of precipitation presents a C-curve with a nose temperature of 850°C during 2h aging treatment. The solution-treated (ST) HNS exhibits the highest pitting corrosion potential because of high nitrogen content in steel, and especially no precipitation. The pitting corrosion resistance of aged HNS decreases because of the formation of aging precipitation which results in the depletion of Cr and Mo in the matrix. The pitting corrosion potentials firstly decrease then increase as the same tendency as the amount of precipitation expect 850°C and 900°C. Double loop electrochemical potentiokinetic reaction (DL-EPR) results show that the change tendency of IGC susceptibility is well consistent with the amount of precipitation of aged HNS for 2h at various temperatures. With prolonging the aging time at 850°C, aged HNS presents more obviously intergranular sensitization due to the formation of aging precipitation which results in the depletion of Cr and Mo.

Effect of Microalloy Elements on Corrosion Resistance of High-Chromium-Containing Ferritic Stainless Steels in Chloride Solutions

CORROSION ◽  
2001 ◽  
Vol 57 (6) ◽  
pp. 547-556 ◽  
Author(s):  
H. Kim ◽  
Y-D. Lee
Keyword(s):  
Corrosion Resistance ◽  
Pitting Corrosion ◽  
Stainless Steels ◽  
Mechanical Damage ◽  
Chemical Compositions ◽  
Inclusion Type ◽  
Electrochemical Tests ◽  
Pitting Corrosion Resistance ◽  
The Matrix ◽  
The Difference

Abstract The effects of inclusions on corrosion resistance of high-Cr-containing ferritic steels were studied using electrochemical tests (anodic polarization and electrochemical noise [EN]) and a ferric chloride (FeCl3) test in chloride solution. For this purpose, the inclusion type and size in the matrix was controlled by the selective addition of alloying elements, their contents, and pickling treatment. Large inclusions such as titanium nitride (TiN), though chemically stable, caused surface cracks at the inclusion/matrix interface during mechanical treatments and decreased pitting corrosion resistance. Soluble inclusions located at the interface were preferentially attacked to form crevices even if the inclusions were as small as a submicron. Meanwhile, submicron inclusions such as Nb, C, or N did not affect pitting corrosion resistance. Unlike the chemical compositions and shape of inclusion, the surface area covered by inclusions did not affect pitting corrosion resistance. Hence, the main factor affecting corrosion resistance was the presence of a crevice, whether it was formed by dissolution or mechanical damage, and not the number of inclusions. EN testing revealed that the experimental alloys deoxidized by Si were more resistant to initial pitting corrosion resistance than those deoxidized by Al, though many steel manufacturers deoxidize stainless steels by Al. The discrepancy was attributed to the difference of the chemical stability and the feasability of crack formation depending on inclusion.

scholarly journals The Pitting Corrosion Behavior of the Austenitic Stainless Steel 308L-316L Welded Joint

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1258
Author(s):  
Jinshan He ◽  
Shiguang Xu ◽  
Wenxin Ti ◽  
Yaolei Han ◽  
Jinna Mei ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Statistical Analysis ◽  
Austenitic Stainless Steel ◽  
Passive Film ◽  
Pitting Corrosion ◽  
Welded Joint ◽  
Weld Zone ◽  
Electrochemical Tests ◽  
Pitting Corrosion Resistance

The pitting corrosion resistance of the austenitic stainless steel 308L-316L welded joint was investigated by electrochemical tests. It is found that the weld zone was the most critical for pits to initiate in the welded joint due to relatively instable passive film with few Mo and inhomogeneous passive film induced by multiple (Mn, Al, and Si) oxides and continuous network of 13.94 vol.% δ ferrites. By statistical analysis, 53.8% pits initiated at (Mn, Al, and Si) oxides, 23.0% in austenite, and 23.2% at interface between ferrite and austenite. In addition, heat-affected zone was prone to have pitting corrosion compared with the base metal since residual strain was much higher in the region.

Sign in / Sign up

Export Citation Format

Share Document