UNS N06625 Nickel Alloy Round Bar Diameter 10 - 300mm Hot Rolled
Custom Cutting in Length
UNS N06625 (also widely recognized as Inconel® 625) is a premium
nickel-chromium-molybdenum alloy renowned for its exceptional
corrosion resistance, high-temperature strength, and excellent
fabricability. The hot-rolled round bars of this alloy, with a
diameter range of 10mm to 300mm and customizable length cutting,
are widely used in demanding industries such as aerospace, oil and
gas, chemical processing, and marine engineering. Below is a
detailed overview of its key attributes, specifications, and
product details:
1. Chemical Composition
The superior performance of UNS N06625 stems from its precisely
controlled chemical composition, which is compliant with
international standards. The typical elemental ranges (by weight
percentage) are as follows:
| Element | Content Range (%) | Primary Function |
|---|
| Nickel (Ni) | 58.0 min | Base metal; provides fundamental corrosion resistance and alloy
stability. |
| Chromium (Cr) | 20.0 - 23.0 | Enhances resistance to oxidation, sulfidation, and aqueous
corrosion. |
| Molybdenum (Mo) | 8.0 - 10.0 | Boosts resistance to pitting, crevice corrosion, and stress
corrosion cracking. |
| Niobium (Nb) | 3.15 - 4.15 | Forms precipitates (e.g., Ni₃Nb) to strengthen the alloy at high
temperatures. |
| Iron (Fe) | 5.0 max | Improves workability without compromising corrosion resistance. |
| Carbon (C) | 0.10 max | Minimized to reduce carbide precipitation and avoid intergranular
corrosion. |
| Silicon (Si) | 0.50 max | Controls melting and casting properties; kept low to prevent oxide
inclusions. |
| Manganese (Mn) | 0.50 max | Aids in deoxidation during production; limited to maintain alloy
purity. |
| Phosphorus (P) | 0.015 max | Reduced to avoid brittleness and improve weldability. |
| Sulfur (S) | 0.015 max | Minimized to prevent hot cracking and enhance corrosion resistance. |
2. Mechanical Properties
UNS N06625 hot-rolled round bars exhibit outstanding mechanical
strength at both room and elevated temperatures, making them
suitable for load-bearing applications in harsh environments. The
following properties are typical for the hot-rolled (annealed)
condition:
| Property | Test Standard | Typical Value (Room Temperature) |
|---|
| Tensile Strength | ASTM B446 | ≥ 795 MPa (115 ksi) |
| Yield Strength (0.2% offset) | ASTM B446 | ≥ 345 MPa (50 ksi) |
| Elongation (in 50mm) | ASTM B446 | ≥ 30% |
| Hardness (Brinell) | ASTM E10 | ≤ 220 HB |
| Impact Strength (Charpy V-notch) | ASTM A370 | ≥ 100 J (74 ft-lb) |
Note: At elevated temperatures (e.g., 650°C/1200°F), the tensile
strength remains above 480 MPa, and yield strength above 275 MPa,
demonstrating excellent high-temperature stability.
3. Similar Grades
UNS N06625 is standardized globally under different designations,
ensuring compatibility with international procurement and
engineering requirements. The key equivalent grades are listed
below:
| Standard System | Grade Designation | Region/Organization |
|---|
| UNS (USA) | UNS N06625 | ASTM (American Society for Testing and Materials) |
| DIN (Germany) | W. Nr. 2.4856 | DIN EN (Deutsches Institut für Normung) |
| EN (Europe) | NiCr22Mo9Nb | CEN (European Committee for Standardization) |
| JIS (Japan) | NCF625 | JIS (Japanese Industrial Standards) |
| GB (China) | NS3306 | GB/T (National Standard of the People’s Republic of China) |
| ISO | ISO 6208: NiCr22Mo9Nb | ISO (International Organization for Standardization) |
4. Product Standards
The manufacturing, testing, and quality control of UNS N06625
hot-rolled round bars adhere to strict international standards to
ensure consistency and reliability. The primary applicable
standards are:
- ASTM B446: Standard Specification for
Nickel-Chromium-Molybdenum-Columbium Alloy (UNS N06625) and
Nickel-Chromium-Molybdenum-Silicon Alloy (UNS N06219) Rod and Bar
- ASTM B564: Standard Specification for Nickel and Nickel Alloy
Forgings (covers forging processes if applicable)
- ASME SB-446: Boiler and Pressure Vessel Code (BPVC) version of ASTM
B446, for pressure-containing applications
- EN 10088-3: European standard for stainless steels and nickel
alloys; specifies requirements for bars and rods
- DIN EN 10088-3: German adoption of EN 10088-3, with additional
regional quality controls
5. Product Specifications & Customization
- Diameter Range: 10mm to 300mm (inclusive). For diameters outside
this range (e.g., <10mm or >300mm), custom manufacturing is
available upon request.
- Processing Method: Hot-rolled. Hot rolling enhances the alloy’s
grain structure, improves mechanical strength, and ensures uniform
density across the bar cross-section.
- Length Customization: Standard lengths include 2000mm, 3000mm, and
6000mm. Custom cutting is offered to any length (e.g., 500mm,
1500mm) with a tolerance of ±1mm, eliminating the need for
secondary cutting by customers and reducing material waste.
- Surface Finish: Hot-rolled surface (mill finish) with a smooth,
scale-free appearance. Optional surface treatments (e.g., pickling,
polishing) are available for applications requiring enhanced
corrosion resistance or aesthetic appeal.
6. Packaging & Shipping
To ensure the round bars remain protected from damage, corrosion,
and contamination during storage and transportation, the following
packaging measures are implemented:
- Inner Protection: Each round bar is individually wrapped in
moisture-resistant kraft paper or plastic film to prevent rusting.
- Outer Packaging: Bars are bundled into wooden crates or steel
pallets (depending on diameter and quantity) for stability. Crates
are reinforced with steel straps to avoid shifting during transit.
- Labeling: Each package is clearly labeled with key information:
alloy grade (UNS N06625), diameter, length, heat number, batch
number, weight, and manufacturer’s logo. This facilitates
traceability throughout the supply chain.
- Shipping Options: Available via sea freight (for bulk orders), air
freight (for urgent orders), or land transportation (for regional
deliveries). Custom packaging for specific shipping requirements
(e.g., export compliance) is also supported.
7. Key Applications
Leveraging its corrosion resistance, high-temperature strength, and
weldability, UNS N06625 hot-rolled round bars are used in:
- Aerospace: Engine components, turbine blades, and structural parts.
- Oil & Gas: Downhole tools, wellhead equipment, and pipelines
(resistant to sour gas and seawater).
- Chemical Processing: Reactors, heat exchangers, and valve stems
(resistant to acids and alkalis).
- Marine Engineering: Propeller shafts, hull components, and offshore
platform structures.
- Power Generation: Boiler tubes, steam turbine parts, and nuclear
reactor components.
In summary, UNS N06625 hot-rolled round bars (10-300mm diameter,
custom length) offer a balance of performance, versatility, and
quality, making them a preferred choice for critical applications
in extreme environments.
