Rating
| Concentration | 20 °C | 50 °C | Remark |
|---|---|---|---|
| 4 % | – | – | |
| 50 % | D | D | |
| 70 % | D | D | |
| 100 % | C* | – |
* estimated rating, given in the source without a temperature
Material comparison at 20 °C
Resistance overview
The resistance of SS 316 to Hydrofluoric Acid is concentration-dependent. Across the 3 tested concentrations (50 %, 70 %, 100 %), the 20 °C rating ranges from C at lower concentrations to D at higher ones. This means engineers must verify which concentration their process actually involves before relying on a single rating. The rating remains stable between 20 °C and 50 °C, which means this material can also handle moderately elevated process temperatures without additional risk.
Application context
Hydrofluoric Acid is commonly encountered in surface cleaning and water treatment. SS 316 (Stainless steel 1.4401 (AISI 316)) is a metal typically used for vessels, heat exchangers, fittings and structural components. Because Hydrofluoric Acid is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.
Practical recommendation
SS 316 is not recommended for use with Hydrofluoric Acid. The D rating indicates that the material will suffer rapid and severe degradation, which may include cracking, dissolution, severe swelling, or complete structural failure. Using this combination risks equipment damage, leaks, and potential safety incidents. Consider using LDPE, PP, PVC Rigid instead, which are rated A for this chemical and offer reliable long-term performance.
Did you know?
The ratings shown here apply to pure Hydrofluoric Acid in contact with the base metal. In real-world applications, additives, pigments, and fillers in the material can shift resistance in either direction.
Materials rated A or B at 20 °C
Based on the row for 70 %, 20 °C.
- Thermoplastics
- PP A, PVC Rigid A, LDPE A
- Fluoropolymers
- PTFE A, PVDF A, FEP A
About SS 316
Stainless steel 316 (1.4401) contains molybdenum, which improves resistance to chlorides over 304. Hydrochloric acid and other halide acids still cause pitting.
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.