These corrosion data are mainly based on results of general corrosion laboratory tests, carried out with pure chemicals and water solutions nearly saturated with air (the corrosion rate can be quite different if the solution is free from oxygen).

All concentrations are given in weight-% and the solvent is water if nothing else is shown. The corrosion data apply to annealed materials with normal microstructure and clean surfaces, throughout.

Nitric acid, HNO3
Conc. %0.51115555510101010202020
Temp. °C2502050100 =BP2050100 =BP1502902050101 =BP1452050103 =BP
Grade or type of alloy:
Carbon steel222222222222222
13 Cr012012220122012
Alleima® 1802000000220002000
Alleima® 3R120000000120002000
Alleima® 3R600000000120002000
18Cr13Ni3Mo 1)
000000120002000
17Cr14Ni4Mo 2)
000000120002000
Alleima® 2RK65 ('904L')0000000120002000
Sanicro® 280000000000
254 SMO000000000
654 SMO000000000
SAF™ 2304000000000
SAF™ 2205000000000
SAF™ 2507000000000
Titanium (CP Ti)0000000000000000

1) ASTM 317L, e.g. Alleima® 3R64
2) EN 1.4439, e.g. Alleima® 3R68

Nitric acid, HNO3
Conc. %20303030305050505050606060606565
Temp. °C1202070106 =BP120207090110117 =BP2060100121 =BP2060
Grade or type of alloy:
Carbon steel2222222222222222
13 Cr20122011ig22012201
Alleima® 180220012001ig1ig2001ig200
Alleima® 3R1210001000ig1ig1ig001ig1ig00
Alleima® 3R6010001000ig1ig1ig001ig1ig00
18Cr13Ni3Mo 1)
10001000ig1ig1ig001ig1ig00
17Cr14Ni4Mo 2)
10001000ig1ig1ig001ig1ig00
Alleima® 2RK65 ('904L')10001000ig0ig1ig000ig1ig00
Sanicro® 28000000ND0ND0ND00
254 SMO1ig00
654 SMO
SAF™ 23040ig00
SAF™ 2205000000ND0ND0ND00
SAF™ 2507000000ND0ND0ND00
Titanium (CP Ti)1001100111001000
SAF™ 29060
SAF™ 2707 HD0
SAF™ 3207 HD

1) ASTM 317L, e.g. Alleima® 3R64
2) EN 1.4439, e.g. Alleima® 3R68

Nitric acid, HNO3
Conc. %65656565808080809090909497999999
Temp. °C7090121 =BP175205080106 =BP208094 =BP3025254084 =BP
Grade or type of alloy:
Carbon steel222222222222222
13 Cr11ig2012202222222
Alleima® 180201ig2001ig202200122
Alleima® 3R1201ig1ig001ig202200122
Alleima® 3R6001ig1ig001ig1ig02200122
18Cr13Ni3Mo 1)
01ig1ig001ig1ig0220122
17Cr14Ni4Mo 2)
01ig1ig001ig1ig02201122
Alleima® 2RK65 ('904L')00ig1ig001ig1ig01ig20122
Sanicro® 2800ig0ig
254 SMO00ig1ig
654 SMO1ig
SAF™ 230400ig1ig11
SAF™ 220500ig1ig
SAF™ 250700ND1ig
Titanium (CP Ti)0000000000000001
SAF™ 29060
SAF™ 2707 HD0
SAF™ 3207 HD0

1) ASTM 317L, e.g. Alleima® 3R64
2) EN 1.4439, e.g. Alleima® 3R68

Nitric acid, HNO3
Temp. °C2540
Grade or type of alloy:
Carbon steel
13 Cr
Alleima® 1802
Alleima® 3R1201
Alleima® 3R6011
18Cr13Ni3Mo 1)
17Cr14Ni4Mo 2)
Alleima® 2RK65 ('904L')
Sanicro® 28
254 SMO
654 SMO
SAF™ 2304
SAF™ 2205
SAF™ 2507
Titanium (CP Ti)22

1) ASTM 317L, e.g. Alleima® 3R64
2) EN 1.4439, e.g. Alleima® 3R68

Symbol clarification

These corrosion tables use a number of symbols, having the following meanings:

Symbol Description
0 Corrosion rate less than 0.1 mm/year. The material is corrosion proof.
1 Corrosion rate 0.1—1.0 mm/year. The material is not corrosion proof, but useful in certain cases.
2 Corrosion rate over 1.0 mm/year. Serious corrosion. The material is not usable.
p, P Risk (severe risk) of pitting and crevice corrosion.
c, C Risk (Severe risk) of crevice corrosion. Used when there is a risk of localised corrosion only if crevices are present. Under more severe conditions, when there is also a risk of pitting corrosion, the symbols p or P are used instead.
s, S Risk (Severe risk) of stress corrosion cracking.
ig Risk of intergranular corrosion.
BP Boiling solution.
ND No data. (Used only where there are no actual data to estimate the risk of localised corrosion instead of p or s).

Disclaimer: Laboratory tests are not strictly comparable with actual service conditions. Accordingly, Alleima makes no warranties, express or implied, and accept no liability, compensatory or consequential, for the performance of different materials in individual applications that may be based on the information provided in this publication.