Hastelloy B2 Plate vs C276: Difference

When selecting a nickel alloy for highly corrosive environments, two names often come up: Hastelloy B2 and Hastelloy C276. Both are premium alloys from Haynes International. But they serve very different purposes.

Hastelloy B2 Plate vs C276 Difference

This article clearly explains the differences between Hastelloy B2 plate and Hastelloy C276.

Hastelloy B2 contains more molybdenum and no chromium. Hastelloy C276 contains chromium and tungsten.

Hastelloy B2 (UNS N10665):

Nickel: ~65%

Molybdenum: ~28%

Chromium: 0% (less than 1%)

Iron: ~2%

Hastelloy C276 (UNS N10276):

Nickel: ~57%

Molybdenum: ~16%

Chromium: ~15.5%

Tungsten: ~3.5%

Iron: ~5.5%

Chromium makes C276 resistant to oxidizing chemicals (like nitric acid or wet chlorine). B2 has no chromium, so it cannot handle oxidizing environments.

Hastelloy B2 resists pure reducing acids (like hydrochloric acid) better than C276, but C276 resists both reducing and oxidizing acids.

Hastelloy B2 is the top choice for hydrochloric acid at all concentrations and temperatures, as well as dilute sulfuric acid. However, it fails quickly in the presence of even tiny amounts of oxidizers (e.g., ferric ions, copper ions, or dissolved oxygen).

Hastelloy C276 is not as strong in pure hydrochloric acid as B2, but it handles mixed acids, chlorides, wet chlorine, and hypochlorite with ease. It is the most versatile corrosion-resistant alloy.

Simple rule:

Only hydrochloric or dilute sulfuric? → B2.

Unknown or mixed chemicals? → C276.

Welding Heat Exposure Difference

Hastelloy B2 is prone to cracking after welding unless strictly controlled; Hastelloy C276 remains stable under most welding conditions.

Hastelloy B2 has a narrow safe temperature range. If heated to 650–870°C (1200–1600°F) during welding or improper heat treatment, it forms brittle intermetallic phases (Ni-Mo precipitates). This ruins ductility and causes weld cracking. To avoid this, B2 must be welded with very low heat input and often requires a post-weld solution anneal.

Hastelloy C276 is much more forgiving. It resists grain boundary precipitate formation during welding. You can weld C276 using standard procedures (TIG, MIG, and SMAW) without special post-weld heat treatment. This is why C276 is the industry workhorse.

If your shop does not have strict welding controls, avoid B2 plates. Use C276.

Hastelloy B2 plates are used almost exclusively in pure reducing acid service; C276 plates appear in a much wider range of industries.

Hastelloy B2 applications:

Hydrochloric acid evaporators and storage tanks

Vacuum dryers for acid chlorides

Reactors for pharmaceutical intermediates (no oxidizing contaminants)

Flue gas desulfurization – but only in oxygen-free zones

Hastelloy C276 applications:

Chemical process vessels for mixed acids (HCl + H2SO4 + chlorides)

Pollution control scrubbers (wet chlorine environments)

Offshore platforms (seawater + H2S)

Nuclear fuel reprocessing

Paper mill bleach plants

If you see B2 in a chemical plant, you know the process is strictly reducing. If you see C276, the process may contain surprises.

Hastelloy C276 has higher tensile strength and better ductility than Hastelloy B2 at room temperature.

Property	Hastelloy B2	Hastelloy C276
Tensile strength (MPa)	760	790
Yield strength (MPa)	350	355
Elongation (%)	40	50
Hardness (HRB)	85	87

In practice, both are strong and formable. However, C276's higher elongation makes it easier to cold-form into complex shapes like dished heads or conical transitions. B2 is slightly more brittle after welding if not properly annealed.

Hastelloy B2 plates are generally 15–25% more expensive than C276 plates per pound.

Cost Difference

Why? B2 contains nearly 28% molybdenum. Molybdenum is costly (often $20–40 per pound). C276 uses only 16% molybdenum plus chromium (cheaper) and tungsten. However, B2's limited demand and specialized manufacturing also keep prices high.

Example price range (as of 2025):

Hastelloy C276 plate: $45–65 per pound

Hastelloy B2 plate: $55–80 per pound

Note: Prices fluctuate with nickel and molybdenum markets. Always request a current quote.

Hastelloy C276 plates are stocked worldwide; Hastelloy B2 plates are special-order in most regions.

C276 is one of the most common nickel alloys. Major distributors (Haynes, Rolled Alloys, High Performance Alloys) keep C276 plate, sheet, bar, and pipe in stock. Lead times: days to weeks.

B2 is a niche product. Most suppliers do not stock B2 plates. You typically order directly from Haynes International or a specialized mill. Lead times: 8–12 weeks.

Advice for buyers: If you need material quickly, choose C276. Only wait for B2 if your process absolutely demands it.

Hastelloy C276 can be welded using common fillers (ERNiCrMo-4); Hastelloy B2 requires matching B2 filler and strict heat control.

C276 welding: Use filler metal ERNiCrMo-4 (same as C276). No preheat. No post-weld heat treatment required. Interpass temperature below 175°C (350°F). Works with TIG, MIG, and stick welding.

B2 welding: Use matching Hastelloy B2 filler (ERNiMo-10). Preheat to 150°C (300°F) maximum. Control interpass temperature carefully. After welding, solution anneal at 1060°C (1950°F) followed by rapid quench. Skip this step – and your weld zone will crack under stress.

Simple conclusion: For most fabrication shops, C276 is the safer, easier choice.

Both materials are governed by strict international engineering standards, but they fall under different certifications that dictate their testing and manufacturing protocols.

Hastelloy B2 Plates: When our facility processes B2, it must strictly adhere to ASTM B333 and ASME SB-333 specifications. These standards ensure the metal is properly melted and rolled to maintain its specific resistance to hydrochloric acid.

Hastelloy C276 Plates: C276 plates are manufactured and certified under ASTM B575 and ASME SB-575. These guidelines verify the exact balance of chromium and tungsten required for its broad-spectrum chemical resistance.

Procurement documents and technical reports must always cite the correct ASTM or ASME specification. Ordering a plate without verifying these specific certifications compromises the structural integrity of the final product.

Speaking as someone who has supplied both alloys for over 15 years:

Hastelloy C276 is the smarter choice for 95% of applications. It is versatile, forgiving to fabricate, and widely available. Only use Hastelloy B2 when you have a long-running, pure hydrochloric acid process with absolute assurance of no oxidation.

When in doubt, call your alloy supplier with your process details. They will help you avoid an expensive mistake.