Page 4 - SD 2205

Localised corrosion resistance
a) Pitting corrosion

°C °F
100 210 104
SD 2205
75 170

50 316 120

25 80
304L
0 0 SD 2205
0.01 0.1 1 Cl %
Sensivity to pitting corrosion ASTM G48A Test results
Effects of temperature and chloride content 10% F Cl 3 6H 2
The high chromium (22%) and molybdenum (3%) combined with 0.16%
nitrogen additions explain why SD 2205 duplex grade behaves particularly well
when considering pitting corrosion resistance. SD 2205 outperforms than 304 and
316L grades, even in very oxydizing and acidic solutions.

b) Crevice corrosion resistance

µA/cm² °C °F
125 35 86
30
100 25 68
20
304
75 15
SD 2205 10 50
50
317
LNM 316L
25
304L 316L SD 2205
Guaranteed Ask us S31803
0.5 1.5 2 pH
Depassivation conditions of several
stainless steels ASTM G78 - Crevice
Solution : 30 g/l NaCl 20°C 10% FeCl 3 6H 2O soluti
The improved crevice corrosion resistance of SD 2205 explains its use in
chloride/fluoride processes containing deposits. Typical applications are Pulp and
Paper industry, Pollution Control equipments, On/Offshore applications.
Stress corrosion cracking resistance

°C °F pH2S
480 1 bars SCC 5% Na Cl pH3 psi 14
Neutral aerated aqueous solution
100 % YS
SD 2205 NACE TM 01 77

SD 2205

120 160°C
Cl %
SSCC resistance in sour gas media
The duplex microstructure is known to improve the stress corrosion cracking
resistance of stainless steels. This is the case in neutral aerated aqueous solutions
containing chlorides and in sour gas conditions in the oil and gas industry. SD 2205
alloy has been extensively used for welded pipes.