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.

Lactic acid, C2H4(OH)COOH
Conc. %11.51.551010202025252530303050
Temp. °C20- 5020100 =BP20- 10020- 100101 =BP80101 =BP20- 5075- 9010020- 7075- 100102 =BP20- 70
Carbon steel112222222222222
13 Cr112222222222222
Alleima® 1802000000000000010
Alleima® 3R12000001010120120
Alleima® 3R60000000000000010
18Cr13Ni3Mo 1)
000000000000010
17Cr14Ni4Mo 2)
000000000000010
Alleima® 2RK65 ('904L')000000000000000
Sanicro® 28000000000000000
254 SMO000000000000000
654 SMO000000000000000
SAF™ 2304000000000000000
SAF™ 2205000000000000000
SAF™ 2507000000000000000
Titanium (CP Ti)000000000000010

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

Lactic acid, C2H4(OH)COOH
Conc. %505075757580808090909090
Temp. °C75-9095-10420-9010011020-95100117=BP204050-100127=BP
Grade or type of alloy:
Carbon steel222222222222
13 Cr222222222222
Alleima® 1802010000010001
Alleima® 3R12120110120122
Alleima® 3R60010000010001
18Cr13Ni3Mo 1)
010000010001
17Cr14Ni4Mo 2)
010000010001
Alleima® 2RK65 ('904L')010000000000
Sanicro® 28000000000000
254 SMO000000000000
654 SMO000000000000
SAF™ 2304000000001
SAF™ 2205000000000000
SAF™ 2507000000000000
Titanium (CP Ti)010010010001

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.