Cobalt-Chrome Alloy Stellite 6B-HR (Hot rolled)
Supply condition
UNS R30016
Thicker plate and bar stock for machined seat rings and wear pads where a mill-finish surface is acceptable.
Values for the HR condition
Other Stellite 6B tempers and conditions
Stellite 6B is listed in 3 conditions; see the grade overview at Stellite 6B.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefault Solution heat treated (mill annealed), plate/bar per AMS 5894 | Standard stocked condition: best combination of toughness and wear resistance for valve seats, wear rings and bushings. | 620 | 1,000 | 8 | 38 HRC | — |
HRThis page Hot rolled | Thicker plate and bar stock for machined seat rings and wear pads where a mill-finish surface is acceptable. | 630 | 1,000 | 7 | 39 HRC | 1.9 % IACS |
Solution treated + precipitation aged | Choose when maximum hardness and abrasive wear life matter more than impact toughness or ductility. | 740 | 1,100 | 3 | 45 HRC | 2 % IACS |
What is Stellite 6B-HR?
Stellite 6B-HR is Stellite 6B supplied in the HR condition — thicker plate and bar stock for machined seat rings and wear pads where a mill-finish surface is acceptable. Stellite 6B-HR has a yield strength of 630 MPa (91.4 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 77% of cobalt-chrome alloy grades. Elongation at break is 7% and the elastic modulus is 230 GPa (33.4 Msi). Stellite 6B-HR has a density of 8.38 g/cm³ (0.303 lb/in³), lighter than 61% of cobalt-chrome alloy grades. It melts at 1,265°C (2,309 °F). SA is the default condition FabDigit quotes; HR is available on request or by drawing note.
Stellite 6B-HR properties
Typical room-temperature values for Stellite 6B-HR; 22 are specific to this condition. Other listed values are Stellite 6B reference data and may not represent this condition. Bars are the position among cobalt-chrome alloy grades.
Physical3
Stellite 6B-HR has a density of 8.38 g/cm³ (0.303 lb/in³), lighter than 61% of cobalt-chrome alloy grades. It melts at 1,265°C (2,309 °F).
Mechanical15
Stellite 6B-HR has a yield strength of 630 MPa (91.4 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 77% of cobalt-chrome alloy grades. Elongation at break is 7% and the elastic modulus is 230 GPa (33.4 Msi).
Thermal6
Stellite 6B-HR is rated for continuous service to 800°C (1,472 °F). It conducts heat at 14.8 W/m·K (8.55 BTU/hr·ft·°F), better than 84% of cobalt-chrome alloy grades. Thermal expansion is 12.5 µm/m·K (6.94 µin/in·°F).
Electrical3
Stellite 6B-HR conducts electricity at 1.9 % IACS, worse than 52% of cobalt-chrome alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), worse than 61% of cobalt-chrome alloy grades.
Sustainability4
Producing a kilogram of Stellite 6B-HR takes about 210 MJ of energy and emits 15 kg of CO₂ — more than 80% of cobalt-chrome alloy grades. Typical recycled content is 25%.
Manufacturability6
Stellite 6B-HR's machinability is not recommended (7/100, worse than 75% of cobalt-chrome alloy grades); weldability poor (25/100); formability not recommended (12/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Stellite 6B-HR
Is Stellite 6B easy to machine?
Treat as a hardfacing alloy: grinding, EDM or waterjet preferred; if turning, use rigid setups, negative-rake carbide/CBN, low speed (5–15 m/min), heavy positive feed and flood coolant to avoid work hardening.
Can Stellite 6B be welded?
GTAW/PTA with matching Stellite 6 filler; preheat 300–500 °C, low heat input and slow cooling to limit carbide-network cracking, stress relieve after welding.
Can Stellite 6B be formed, bent or molded?
Hot form at 1050–1150 °C; cold forming limited to gentle bends in thin annealed strip with generous radii — the carbide network cracks under tight bends.
What surface finishes work on Stellite 6B?
Lapped/ground to mirror seal faces; no anodizing (non-aluminium); passivates naturally through its 30 % Cr, so plating or coating is rarely needed.
Stellite 6B chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cforms Cr7C3/M23C6 carbides | 0.9 – 1.4 | 1.1 |
| Cr | 28 – 32 | 30 |
| W | 3.5 – 5.5 | 4.5 |
| Ni | ≤ 3 | 1.5 |
| Fe | ≤ 3 | 1.5 |
| Si | ≤ 2 | 0.7 |
| Mn | ≤ 2 | 1.4 |
| Mo | ≤ 1.5 | 0.5 |
| Cobalance, ~57–60 % | balance | — |
Stellite 6B-HR — frequently asked
What is Stellite 6B-HR used for?
Stellite 6B-HR is typically used for valve seat rings, wear rings and check valve components. In short: wrought, formable Stellite; ductile hardfacing alloy; sheet and strip availability.
What is the yield strength of Stellite 6B-HR?
Stellite 6B-HR has a typical yield strength of 630 MPa (91.4 ksi) and a tensile strength of 1,000 MPa (145 ksi) — stronger than 77% of cobalt-chrome alloy grades. Strength varies by condition: see the 3 listed tempers.
Is Stellite 6B-HR easy to machine?
Not especially — machinability is rated not recommended (7/100, worse than 75% of cobalt-chrome alloy grades). Treat as a hardfacing alloy: grinding, EDM or waterjet preferred; if turning, use rigid setups, negative-rake carbide/CBN, low speed (5–15 m/min), heavy positive feed and flood coolant to avoid work hardening.
Can Stellite 6B-HR be welded?
Not readily — weldability is rated poor (25/100). GTAW/PTA with matching Stellite 6 filler; preheat 300–500 °C, low heat input and slow cooling to limit carbide-network cracking, stress relieve after welding.
What surface finishes work on Stellite 6B-HR?
Lapped/ground to mirror seal faces; no anodizing (non-aluminium); passivates naturally through its 30 % Cr, so plating or coating is rarely needed.
Can Stellite 6B-HR be formed, bent or molded?
Hot form at 1050–1150 °C; cold forming limited to gentle bends in thin annealed strip with generous radii — the carbide network cracks under tight bends.
What is the maximum service temperature of Stellite 6B-HR?
Stellite 6B-HR is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Stellite 6B-SA and Stellite 6B Aged?
SA is the default condition — standard stocked condition: best combination of toughness and wear resistance for valve seats, wear rings and bushings. Aged: choose when maximum hardness and abrasive wear life matter more than impact toughness or ductility. Yield strength is 620 MPa in SA versus 740 MPa in Aged.
Sources
- AMS 5894 — Cobalt Alloy, Corrosion and Heat Resistant, Sheet, Strip, Plate and Bar (Stellite 6B, UNS R30016) — SAE International (2018)
- Stellite 6B wrought alloy technical data — Kennametal Stellite / Deloro (2021)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Cobalt-base wear alloys) — ASM International (1990)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.