Alloy 59 (UNS N06059 / Nicrofer 5923 hMo) – Supplier of Round Bars, Seamless Tubes & Plates | Shanghai Hangbo Alloy Group

By Shanghai Hangbo Alloy Group Co., Ltd. | ISO 9001:2015 | Est. 2012 | Shanghai, China

Contact: sales@hangboalloy.com | hangbo@nickel-alloy.com | WhatsApp: +86 13611656360

Quick Answer: What Is Alloy 59?

Alloy 59 (UNS N06059 / W.Nr. 2.4605), also marketed as Nicrofer 5923 hMo, is a premium nickel-chromium-molybdenum superalloy widely considered the ultimate single-alloy solution for the broadest spectrum of corrosive environments. With approximately 23% chromium, 16% molybdenum, and critically low iron (≤1.5%) and silicon (≤0.1%) levels, Alloy 59 delivers superior performance in both oxidizing and reducing media simultaneously — outperforming both C-276 and C-22 in mixed-acid chemical processing. Shanghai Hangbo Alloy Group supplies Alloy 59 in precision round bars, seamless tubes, and plates with full EN 10204 3.1 material traceability.

Key Properties at a Glance

The Purity Advantage: Why Fe & Si Contamination Destroys Corrosion Resistance

Alloy 59 is not just "another Ni-Cr-Mo alloy." It represents a step-change in metallurgical purity. Here's why that matters to your bottom line.

Pain Point 1: The Iron Trap in Standard Hastelloy Grades

Standard C-276 allows up to 7% iron and 0.08% silicon. These elements are not just inert "filler" — they form microscopic iron-rich precipitates that act as initiation sites for pitting corrosion in hot chloride environments. Alloy 59 caps iron at ≤1.5% and silicon at ≤0.1%, producing a metallurgically "cleaner" matrix in which pitting simply has no place to start.

Pain Point 2: "I need C-276 for the HCl feed, but the oxidation step destroys it."

This is the most common failure mode we see in batch chemical reactors: C-276 handles the reducing HCl feed perfectly, but when the reactor is opened for cleaning and exposed to atmospheric oxygen + residual acid, the 16% chromium passive film breaks down. Alloy 59's 23% Cr + ≤1.5% Fe combination makes this oxidation resistance intrinsic — it handles both steps without degradation. You can standardize your entire reactor fleet on one alloy.

Pain Point 3: Weld decay in thick-section fabrications

Thick-section (≥25mm) Alloy 59 weldments retain their corrosion resistance in the as-welded condition because the ultra-low carbon (≤0.01%) and silicon prevent carbide precipitation at the grain boundaries. This eliminates the cost and time of post-weld solution annealing for large vessel fabrications — a $15,000–50,000 savings per vessel depending on size.

How Shanghai Hangbo Delivers Alloy 59 at the Purity You're Paying For

Product Overview

Alloy 59 (UNS N06059 / Nicrofer 5923 hMo) was developed by VDM Metals specifically to address the "iron problem" that limited earlier Ni-Cr-Mo grades. By reducing iron 5-fold compared to C-276 (from ≤7% to ≤1.5%) and silicon 8-fold (from ≤0.08% to ≤0.01% target), the matrix becomes essentially a pure Ni-Cr-Mo solid solution. This purity translates into: (1) higher PREN, (2) lower passive current density, and (3) demonstrably longer service life in mixed-acid environments.

Shanghai Hangbo Alloy Group (est. 2012) supplies Alloy 59 to chemical plants, pharmaceutical manufacturers, and pollution control system builders across 32 countries. ISO 9001:2015 certified, with VdTÜV material approval available on request.

Executive Standards

Chemical Composition (wt.% per ASTM B574)

Buyer's verification: Check Fe ≤1.5% and Si ≤0.10% on the MTC. If Fe reads 5–6%, you've been supplied C-276 or C-22, not Alloy 59.

Mechanical Properties

Heat Treatment

• Solution Annealing: 1100 °C – 1180 °C (2012 °F – 2156 °F)
• Cooling: Water quench mandatory. The ultra-low silicon content means secondary phases precipitate faster than in C-276 if cooling is delayed.
• Post-Weld Heat Treatment: Not required for wall thickness ≤25mm. For thicker sections, a brief solution anneal is recommended.
• Grain Size: ASTM No. 4–6.

Industry Applications

Quality Assurance: 7-Stage Protocol

1. OES Verification: Fe ≤1.5%, Si ≤0.10% confirmed per heat.
2. VdTÜV Traceability: Material approval documentation available.
3. 100% UT: Per ASTM A388 on all bars.
4. 100% ECT: Every seamless tube tested for surface integrity.
5. Hydrostatic Test: All tubular products at 1.5× rated pressure.
6. Mechanical Test: Tensile/yield/elongation certified per ASTM B574.
7. Heat-Number Traceability: Permanent marking + EN 10204 3.1 MTC.

FAQ

Q1: What is Alloy 59 used for?

Multi-purpose chemical reactors, pharmaceutical CIP equipment, FGD scrubbers, and any environment cycling between oxidizing and reducing conditions where C-276 alone would fail.

Q2: What is the density?

8.6 g/cm³ (0.311 lb/in³).

Q3: What makes Alloy 59 different?

Ultra-low iron (≤1.5%) and silicon (≤0.1%) create the metallurgically purest Ni-Cr-Mo matrix available, eliminating pitting initiation sites present in C-276 and C-22.

Q4: What is the max service temperature?

1040 °C for oxidation resistance; ~425 °C for structural aqueous corrosion.

Q5: What is the tensile strength?

≥ 690 MPa (100 ksi) in the annealed condition.

Q6: What is the yield strength?

≥ 340 MPa (49 ksi) — higher than C-276 (283 MPa).

Q7: What is the elongation?

≥ 40% — excellent for cold forming.

Q8: What is the price per kg?

Approximately $42–95 USD/kg. Contact sales@hangboalloy.com for a real-time quote.

Q9: Is Alloy 59 weldable?

Yes — excellent weldability with matching ERNiCrMo-13 filler. Ultra-low C + Si enable as-welded service up to 25mm thickness.

Q10: How does it compare to C-276 and C-22?

Alloy 59 combines C-276's reducing acid resistance with C-22's oxidizing resistance, and adds superior pitting resistance through its ultra-pure matrix. It is often described as "C-276 and C-22 in one material."

Q11: What forms does Shanghai Hangbo supply?

Round bars (6–400mm), seamless tubes (OD 6–219mm), plates (1–100mm), sheets, custom forgings.

Q12: How to verify genuine Alloy 59?

Check Fe ≤1.5% and Si ≤0.10% on the MTC. PMI on arrival. If Fe is 5–7%, it's C-276 or C-22, not Alloy 59.

Q13: Does Shanghai Hangbo ship internationally?

Yes — 32 countries. DDP/DAP/FOB/CIF available.

Contact Shanghai Hangbo Alloy Group

Shanghai Hangbo Alloy Group Co., Ltd. — Founded 2012 | ISO 9001:2015 | The Metallurgical Purity Specialist | 32 Countries