Alloy 20 vs Hastelloy C-276: Sulfuric Acid
Date: 2026年9月13日 Categories: News Views: 360
By Shanghai Hangbo Alloy Group Co., Ltd. - China Supplier | ISO 9001:2015 | Est. 2012
Contact: sales@hangboalloy.com | hangbo@nickel-alloy.com | WhatsApp (Lisa): +86 13611656360
Quick Answer: What Is the Difference Between Alloy 20 and Hastelloy C-276?
Alloy 20 (UNS N08020, also known as Carpenter 20Cb-3) is an iron-nickel-chromium alloy with copper and molybdenum, engineered specifically for sulfuric acid service. Hastelloy C-276 (UNS N10276) is a nickel-chromium-molybdenum alloy with tungsten, covering a much broader corrosion envelope including hot hydrochloric acid, chlorides, and mixed acids. Alloy 20 costs roughly half of C-276 and is excellent for sulfuric acid up to moderate temperatures; C-276 handles the aggressive, chloride-bearing, and hot acid duties where Alloy 20 fails. Rule: clean H2SO4 → Alloy 20; chlorides/hot HCl/mixed acids → C-276.
Composition Comparison (wt.%)
| Element | Alloy 20 (N08020) | Hastelloy C-276 (N10276) |
|---|---|---|
| Nickel | 32-38 | Balance |
| Chromium | 19-21 | 14.5-16.5 |
| Molybdenum | 2.0-3.0 | 15-17 |
| Copper | 3.0-4.0 | -- |
| Tungsten | -- | 3-4.5 |
| Iron | Balance (~37%) | 4-7 |
| Niobium | 1.0 max (8xC min) | -- |
Key: Alloy 20's copper makes it uniquely good in sulfuric acid; C-276's tungsten + 16% Mo give broad aggressive-acid coverage.
Corrosion Performance Comparison
| Environment | Alloy 20 | Hastelloy C-276 | Better |
|---|---|---|---|
| H2SO4 (20-50%, moderate temp) | Excellent | Excellent | Alloy 20 (cost) |
| H2SO4 (hot, concentrated) | Moderate | Excellent | C-276 |
| HCl (any concentration) | Poor | Excellent | C-276 |
| Chlorides / pitting | Moderate | Excellent | C-276 |
| HNO3 (nitric) | Good | Good | Tie |
| Mixed acid + chloride | Moderate | Excellent | C-276 |
| Phosphoric acid | Good | Excellent | C-276 |
Mechanical Properties (Annealed, RT)
| Property | Alloy 20 | Hastelloy C-276 |
|---|---|---|
| Tensile Strength | 550-620 MPa | >= 690 MPa |
| Yield Strength | 240-310 MPa | >= 285 MPa |
| Elongation | 30-45% | >= 40% |
Which One for Your Application?
| Application | Best Choice | Why |
|---|---|---|
| Sulfuric acid piping | Alloy 20 | Purpose-built + cost |
| Sulfuric acid pumps | Alloy 20 | Proven performance |
| Mixed acid with chlorides | C-276 | Chloride resistance |
| HCl handling | C-276 | Only viable option |
| FGD scrubbers | C-276 | Chloride + acid |
| Pickling tank internals | Alloy 20 | Acid + economics |
Price Comparison (2026, EXW)
| Form | Alloy 20 | Hastelloy C-276 |
|---|---|---|
| Plate | \$26-40/kg | \$58-88/kg |
| Round Bar | \$25-38/kg | \$55-85/kg |
| Tube | \$32-48/kg | \$68-105/kg |
C-276 costs about twice as much as Alloy 20 — use Alloy 20 wherever it is technically adequate.
FAQ
Q1: Is C-276 better than Alloy 20?
Technically broader, but far more expensive. For clean sulfuric acid, Alloy 20 is the cost-effective standard.
Q2: Why is Alloy 20 good in sulfuric acid?
Its 3-4% copper addition stabilizes the passive film in sulfuric acid solutions.
Q3: What are the UNS numbers?
N08020 = Alloy 20; N10276 = Hastelloy C-276.
Q4: Which handles hydrochloric acid?
Only C-276 — Alloy 20 has poor HCl resistance.
Q5: How much cheaper is Alloy 20?
Roughly half the price of C-276.
Q6: Which for mixed acids?
C-276, due to its molybdenum and tungsten content.
Q7: What does Shanghai Hangbo supply?
Both grades in plates, bars, tubes, and fittings with EN 10204 3.1 certification. SGS/TUV/BV available.
Contact & Complete Product Range
Shanghai Hangbo Alloy Group Co., Ltd. - China Supplier
Email: sales@hangboalloy.com | WhatsApp (Lisa): +86 13611656360 | www.nickel-alloy.com
All Grades
Ni: NI200-N6 | Monel: 400-502, K-500, R-405 | Inconel: 600-740H, X-750, 725 | Incoloy: 800-27-7MO | Hastelloy: C-276-HYBRID-BC1, N | Super Austenitic: 904L-AL-6XN | Chromium-Rich: Alloy 33 | High-Strength Stainless: Nitronic 50/60, PH13-8Mo | Chlorination: Alloy 45 | Nimonic: 75-263 | Haynes: 25-HR-160 | RA: 330/333 | Precision: 1J22-4J45 | High-Strength: 18Ni250-AerMet100 | Heating: Cr20Ni80/60 | Specialty: Alloy 20-602CA
Product Forms: Bars(6-500mm) | Tubes(OD 6-610mm) | Plates(0.1-100mm) | Forgings | Welded Pipes | Fittings | Wire(0.05-10mm) | Strip(0.02-4.0mm)
SGS/BV/TUV. www.nickel-alloy.com
