Rating
| Concentration | 20 °C | 50 °C | Remark |
|---|---|---|---|
| concentration not stated | C | C | pitting risk; corrected, see below |
Corrected and disputed values
- SS 304 (concentration not stated): source value 1/3L, shown as 3/3L. Stainless steel 304 pits in seawater. The Australian Stainless Steel Development Association limits it to fittings that are regularly washed with fresh water, and two charts rate it C. The source rates it A at 20 °C. [1] [2] [3]
Source values use the scale 1 (very good) to 4 (not resistant); 1 = A, 4 = D.
Material comparison at 20 °C
Resistance overview
SS 304 has limited resistance (C) to Seawater (Salt Water) at 20 °C. This indicates that the chemical has a noticeable effect on the material, which may include visible swelling, softening, or a measurable loss of tensile strength. Use is generally limited to short-term or intermittent contact where full structural integrity is not required. The rating remains stable between 20 °C and 50 °C, which means this material can also handle moderately elevated process temperatures without additional risk. Note that the source flags a risk of pitting or stress-corrosion cracking for this combination, which is particularly relevant for pressure-bearing or structurally loaded components.
Application context
Seawater (Salt Water) is commonly encountered in electroplating and de-icing. SS 304 (Stainless steel 1.4301 (AISI 304)) is a metal typically used for vessels, heat exchangers, fittings and structural components. The compatibility between these two is therefore an important consideration for engineers and procurement teams selecting containment, transfer, or processing equipment.
Practical recommendation
SS 304 has limited resistance to Seawater (Salt Water) and should only be used for short-term or intermittent contact at ambient temperature. The C rating means the material undergoes noticeable changes — swelling, loss of strength, or surface degradation — that make it unsuitable for permanent installations. For prolonged or continuous exposure, HDPE, LDPE, Nylon (PA) offer significantly better resistance and are rated A.
Did you know?
Stainless steel 1.4301 (AISI 304) was first developed in the 1910s and remains one of the most widely used metals in chemical handling equipment.
Materials rated A or B at 20 °C
- Thermoplastics
- HDPE A, PP A, PVC Rigid A, LDPE A, Nylon (PA) A, Acetal (POM) A, Polycarbonate A, PVC Flexible A, Polystyrene A, PETG A, SAN A
- Fluoropolymers
- PTFE A, PVDF A, FEP A, ECTFE/ETFE A
- Elastomers
- EPDM A, Viton (FPM) A, NBR A
- Metals
- SS 316 B
About SS 304
Stainless steel 304 (1.4301) resists oxidising acids and most organic chemicals. Chlorides cause pitting and stress-corrosion cracking.
Rating scale
- A very good resistance
- B good resistance
- C limited resistance
- D not resistant
- – no data
- K no general statement possible
A rating marked * is an estimate in the source, not a test result. An estimate is given as one value without a temperature.
About this data
The ratings come from the chemical resistance list published by Bürkle GmbH, which compiled them from raw-material manufacturers’ data. They describe laboratory tests on the raw material at 20 °C and 50 °C.
A finished part also sees pressure, mechanical stress, welds and mixtures that a laboratory test does not. Treat the rating as a first filter and test under your own conditions before relying on it.