Hangbo Alloy Group
Shanghai · Est. 2012
UNS R30006 / W.Nr. 2.4882 — Chemical composition, mechanical properties, temperature limits, corrosion resistance, and applications for engineers and procurement professionals.
Stellite 6B (UNS R30006 / W.Nr. 2.4882) is a wrought cobalt-chromium-tungsten alloy renowned for its exceptional resistance to wear, galling, cavitation, and corrosion. Developed by Haynes International, it is the wrought counterpart to the cast Stellite 6 grade and offers a unique combination of toughness and hardness that makes it ideal for components subjected to sliding wear, erosion, and thermal shock. With approximately 30% chromium and 4.5% tungsten in a cobalt matrix, Stellite 6B retains useful hardness and strength at temperatures up to 815 °C.
The chemical composition of Stellite 6B is carefully controlled to balance high-temperature strength, corrosion resistance, and fabricability. The primary strengthening and corrosion-resisting elements are tightly specified in applicable aerospace and ASTM standards.
| Element | Min % | Max % |
|---|---|---|
| Cobalt (Co) | Balance | Balance |
| Chromium (Cr) | 28.0 | 32.0 |
| Tungsten (W) | 3.50 | 5.50 |
| Nickel (Ni) | — | 3.0 |
| Iron (Fe) | — | 3.0 |
| Carbon (C) | 0.90 | 1.40 |
| Manganese (Mn) | — | 2.0 |
| Silicon (Si) | — | 2.0 |
| Molybdenum (Mo) | — | 1.50 |
| Phosphorus (P) | — | 0.04 |
| Sulfur (S) | — | 0.03 |
Stellite 6B exhibits a stable microstructure that retains useful physical properties across a wide temperature range, supporting its use in thermally cyclic and high-temperature applications.
| Property | Value | Unit |
|---|---|---|
| Density | 8.39 | g/cm3 |
| Melting Point | 1280-1395 | °C |
| Specific Heat (21 °C) | 372 | J/kg·K |
| Thermal Conductivity (21 °C) | 14.8 | W/m·K |
| Electrical Resistivity (21 °C) | 0.90 | μΩ·m |
| Modulus of Elasticity (21 °C) | 250 | GPa |
| Mean Coefficient of Thermal Expansion (21-538 °C) | 14.2 | μm/m·°C |
Mechanical properties depend on product form and heat treatment condition. Values below represent typical solution-treated and aged bar or forging stock.
| Property | Value |
|---|---|
| Tensile Strength | 1010 MPa (147 ksi) |
| Yield Strength (0.2% offset) | 655 MPa (95 ksi) |
| Elongation in 2 inches | 7% |
| Hardness (Rockwell C) | 38-44 HRC |
| Hardness (annealed) | 33-43 HRC |
| Izod Impact Strength | 30 J |
Stellite 6B maintains high strength and creep resistance at elevated temperatures, making it suitable for gas turbine hot-section and aerospace structural components.
| Temperature (°C) | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
|---|---|---|---|
| 21 (Room) | 1010 | 655 | 7 |
| 316 | 895 | 565 | 8 |
| 427 | 860 | 520 | 9 |
| 538 | 760 | 450 | 10 |
| 649 | 655 | 380 | 11 |
| 760 | 450 | 275 | 14 |
Stellite 6B provides reliable corrosion resistance in a range of aggressive environments. Performance is governed by the alloy's chromium, molybdenum, cobalt, and nickel contents and by the protective surface oxides formed during service.
The combination of high strength, temperature capability, and environmental resistance makes Stellite 6B suitable for demanding industrial and aerospace applications:
Hangbo Alloy Group manufactures and supplies Stellite 6B in the following product forms, conforming to ASTM, AMS, and other applicable specifications:
| Standard | Description |
|---|---|
| ASTM F90 | Wrought Cobalt-28Chromium-6Molybdenum Prosthesis Alloy (composition basis for Stellite 6B) |
| AMS 5894 | Cobalt Alloy Bars, Forgings, and Rings |
| AWS A5.13 / A5.21 | Surfacing electrodes and rods for hardfacing applications |
| DIN 2.4882 | Wrought cobalt-chromium-tungsten alloy bar and plate |
Stellite 6B is a wrought cobalt-chromium-tungsten alloy valued for its outstanding wear, galling, and corrosion resistance at temperatures up to about 815 °C.
Typical as-supplied hardness is 38-44 HRC; annealed material ranges from 33-43 HRC depending on cross-section and processing.
Cobalt is balanced with approximately 28-32% chromium, 3.5-5.5% tungsten, up to 3% nickel and iron, and 0.9-1.4% carbon.
ASTM F90, AMS 5894, AWS A5.13/A5.21 for hardfacing, and DIN W.Nr. 2.4882.
It is difficult to machine conventionally; grinding, EDM, and specialized carbide tooling are preferred. Finish grinding is the most common sizing method.
Short-term exposure up to 870 °C is possible; long-term service is generally limited to about 815 °C.
Cobalt alloys command a premium over nickel grades; bar and plate pricing depends on cobalt market price, size, finish, and order quantity. Contact us for a quotation.
Flat plate, sheet, round bar, rod, custom forgings, rings, discs, and hardfacing consumables.
It can be welded with similar-composition filler metals, but preheat and controlled interpass temperatures are required to prevent cracking. Hardfacing overlays are common.
Stellite 6B offers better toughness and impact resistance than Stellite 1, with slightly lower hardness; Stellite 12 provides a middle ground between hardness and toughness.
Standard bars and plates are often available from stock; custom forgings typically require 3-6 weeks with MOQs starting at one piece or 50 kg.
Valve seats, balls, gates, and trim in oil & gas; steam turbine components; pump wear parts; and cutting/edging tools.
Hangbo Alloy Group maintains supply channels for Stellite 6B in standard and custom product forms. We provide mill test certificates, third-party inspection reports (SGS, TUV), and custom processing services including cutting, machining, grinding, and surface finishing.
For quotations, material certifications, or technical consultation, contact our sales team or call +86-136-1165-6360. We typically respond within 10 minutes.
Request a quotation for Stellite 6B round bars, tubes, plates, or forgings. We stock standard sizes and accept custom orders.