Page 4 - SD 2507Cu

Chloride 1 g/l 5 g/l 300 g/l
level 30 g/l
F- (ppm) 0 400 1000 0 400 1000 0 400 1000 0 400 1000

6
UR 45N +
UNS 31803 - PREN  35
4 UNS 32550/S32520
+
pH UR 52N
UNS 32550/S32520
2 UNS 08926 - UR B26
UR 52N +
1 N06022 - H.C22 N10276 - H.C276

MATERIAL GUIDE FOR USING IN FGD EQUIPMENTS - 60°C (140°F)
Based on extensive tests results

Pitting and crevice corrosion
The minimum PREN value of 40 also explains why the alloy is highly resistant to
pitting corrosion and crevice corrosion. The alloy behaves much better than 904L
and is, for pitting corrosion resistance, nearly equivalent to 6 Mo super  grade. In
some cases, the crevice corrosion resistance is slightly higher than 6 Mo alloys
due to the 25% Cr additions.

mV/SCE Repassivation potential (1 mA/cm²)
1000 NaCl 30 g/l mV/SCE
1000
800 800 UNS S32550
UNS S32520

600 UR 52N+ 600 UR B6
904 L
UR 35N 400
400
UR B6 UR 52N 200
904L
200 0
316 UNS
S31803
20 40 60 80 100 °C -200 20 40 60 80 100 °C
70 105 140 175 210 °F 70 105 140 175 210 °F
Pitting potential taken from polarization curves Repassivation potential in 15% NaCl solution
for different stainless steels CO 2 saturated
°F
°F
80 ° DUPLEX SUPER-AUSTENITICS 175 80 ° DUPLEX SUPER-AUSTENITICS 175

70 Ask Us 70 Ask Us
Guaranteed
60 Guaranteed 140 60 140
50 50
40 105 40 105
30 30
20 70 20 70
10 10
0 0
UR 35N S32304 UR 45N S31803 UR 52N+ S32520 316L UR B6 904L UR B26 08926 UR 35N S32304 UR 45N S31803 UR 52N+ S32520 316L UR B6 904L UR B26 08926

Test ASTM G48A PITTING in a 6% FeCl 3 solution Test ASTM G78 CREVICE in a 6% FeCl 3 solution
°C °F Crevice area %
11,5% H2SO4 + 1,2% HCl 80 Medium - Cl- 4000ppm + CaS04 7%
+ 1% FeCl3 + 1% CuCl2 Fe (SO4)3 0,7% : pH = 1 aerated
60 UR52N+ 140 T = 60°C Test duration 15 days
60
UR45N 0 ppm F -
40 105 -
40 400 ppm F
317LNM
316
20 70 20

0
316 L 317 LNM UR 45N N08904 UR 52N +
Pollution control equipments
Crevice corrosion test on samples fitted with
GREEN DEATH - CRITICAL PITTING TEMPERATURE multi-crevice washers - effect of fluoride content