Here's a professional comparison of Hastelloy C276 equivalent materials across international standards and functional alternatives:
1. Direct Equivalent Grades by Standard
| Standard | Equivalent | Key Differences |
|---|---|---|
| UNS | N10276 | Same alloy (most common designation) |
| EN (EU) | NiMo16Cr15W (2.4819) | Nearly identical composition |
| ISO | NiMo16Cr15Fe6W4 | Slightly broader element ranges |
| JIS (Japan) | NW 0276 | Matches UNS N10276 |
| GB (China) | NS3304 | Minor tolerance variations |
2. Functional Alternatives for Specific Applications
| Material | Best For | Trade-offs vs. C276 |
|---|---|---|
| Hastelloy C22 (UNS N06022) | Wider temp range & better weldability | Higher cost (~15-20%) |
| Inconel 625 (UNS N06625) | High strength needs | Less Mo (8% vs. 15-17%) → lower pitting resistance |
| Hastelloy B3 (UNS N10675) | Superior HCl resistance | Poor oxidant resistance |
| Zeron 100 (Super Duplex) | Chloride environments | Limited to 300°C |
3. Chemical Composition Comparison (wt%)
| Element | C276 | C22 | Inconel 625 |
|---|---|---|---|
| Ni | Bal. | Bal. | Bal. |
| Mo | 15-17 | 12-14 | 8-10 |
| Cr | 14.5-16.5 | 20-22.5 | 20-23 |
| Fe | 4-7 | 2-6 | ≤5 |
| W | 3-4.5 | 2.5-3.5 | - |
| Co | ≤2.5 | ≤2.5 | ≤1 |
4. Critical Performance Factors
Temperature Limits:
C276: -196°C to 1093°C (oxidizing) / 400°C (reducing)
C22: Extends to 1200°C in oxidizing
625: Best for cryogenic (-270°C)
Corrosion Resistance:
Best for HCl: B3 > C276 > C22
Best for H₂SO₄: C22 ≈ C276 > 625
Best for NaCl: C276 > Zeron 100 > 625
5. Industry-Specific Recommendations
Chemical Processing: Stick with C276 for mixed acid service
Oil & Gas (Sour): C276 or C22 for H₂S/Cl⁻
Pharmaceutical: Consider electropolished C22 for cleanability
Marine: Zeron 100 for seawater pumps
6. Cost Comparison (Indexed to C276=100)
C276: 100
C22: 115-120
625: 90-95
B3: 85-90
Zeron 100: 70-75
7. Key Selection Criteria
When substituting C276:
Verify chloride ion concentration (critical for SCC)
Check pH/temperature profile
Consider fabrication needs (C22 welds easier)
Review industry norms (e.g., NACE MR0175 for oilfield)
For exact equivalency in regulated projects, always:
Request ASTM B575/B574 certs
Validate with corrosion testing
Consult ASME Sec II-D allowable stresses
Need help selecting? Provide:
① Service environment ② Temp/pressure ③ Fabrication method
We'll recommend the optimal alloy.
