Compatibility Rating
📊 Note: Phosphoric Acid resistance varies by concentration. Data available for: 1-5 %, 20%, 30 %, 85 %. Search for specific concentrations →
Why is SS 304 resistant to Phosphoric Acid?
SS 304 shows excellent resistance to Phosphoric Acid due to its chromium content (18%) forming a passive oxide layer resistant to many corrosive environments.
⚠️ When NOT to use SS 304
Avoid using Stainless Steel 304 with chloride-rich environments (seawater, HCl) which cause pitting corrosion. Use 316 grade for chloride exposure.
Comparison Table — All Materials for Phosphoric Acid
| Material | 20°C | 50°C |
|---|---|---|
| HDPE | A | A |
| LDPE | A | A |
| PP | A | A |
| PTFE | A | A |
| PVDF | A | A |
| FEP | A | A |
| ECTFE/ETFE | NR | NR |
| EPDM | A | NR |
| Viton (FPM) | A | A |
| NBR | C | C |
| Silicone | NR | NR |
| SS 316 | A | B |
| SS 304 | A | C |
| Aluminium | D | D |
| PVC Rigid | NR | NR |
| PVC Flexible | NR | NR |
| PMP | NR | NR |
| Polystyrene | NR | NR |
| SAN | NR | NR |
| Polycarbonate | B | B |
| PETG | NR | NR |
| Acetal (POM) | D | D |
| Nylon (PA) | D | D |
| Polysulfone | NR | NR |
A=Excellent · B=Good · C=Fair · D=Poor · NR=No Data
🌡️ Temperature Note
Performance degrades significantly at higher temperatures — rated Excellent at 20°C but only Fair at 50°C. For elevated temperatures, consider a more resistant material. Max service temp: 800°C.
🔄 Better Alternative?
Consider: SS 316 for chloride environments. View all materials for Phosphoric Acid →
FAQ
Is Stainless Steel 304 resistant to Phosphoric Acid?
Stainless Steel 304 has Excellent (A) resistance to Phosphoric Acid at 20°C.
Can I store Phosphoric Acid in Stainless Steel 304?
Yes, Stainless Steel 304 is rated A for Phosphoric Acid.
📊 Note: Phosphoric Acid resistance varies by concentration. Data available for: 1-5 %, 20%, 30 %, 85 %. Search for specific concentrations →