Cobalt-Chrome Alloy Stellite 12
UNS R30012
Stellite 12 is an intermediate-carbide Co-Cr-W hardfacing alloy (UNS R30012) sitting between Stellite 6 and Stellite 1, with about 48 HRC, 800 MPa tensile strength and 1 % elongation.
Reference datasheet — Stellite 12 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Stellite 12 tempers and conditions
Stellite 12 is supplied in 3 conditions, soft to hard.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As cast | Pick for solid wear parts (bushings, nozzles, cutting blades) or as feedstock rod for oxy-fuel/GTAW hardfacing. | 650 | 830 | 1 | 47 HRC | 2 % IACS |
Laser cladding / DED deposit | Best choice for minimal dilution, fine carbide structure and tight heat-input control on precision components. | 700 | 880 | 0.8 | 51 HRC | 1.9 % IACS |
Hot isostatic pressed | Use when a fully dense, isotropic fine-carbide near-net-shape part with better toughness than casting is required. | 700 | 900 | 2 | 49 HRC | 2 % IACS |
Supply forms, finishes and certifications
Ways Stellite 12 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
GTAW | GTAW/TIG deposit from bare cast rod | Surface finish |
OAW | Oxy-acetylene (gas) deposit, low dilution | Surface finish |
SMAW | Covered electrode deposit | Surface finish |
HVOF | HVOF thermal-spray coating | Coating |
PTADefault | Plasma transferred arc powder deposit | Coating |
What is Stellite 12?
Stellite 12 is an intermediate-carbide Co-Cr-W hardfacing alloy (UNS R30012) sitting between Stellite 6 and Stellite 1, with about 48 HRC, 800 MPa tensile strength and 1 % elongation. Engineers choose it when a single overlay must resist both abrasion and moderate impact; it is available as castings, cast rod, electrodes, HIP powder and PTA/GTAW/OAW/SMAW/laser-clad and HVOF deposits, with service to 800 °C. It remains crack-sensitive in thick single-pass beads (weldability rating 40) and can only be finished by grinding or EDM. Move to Stellite 6B for wrought forms or Stellite 1 for maximum wear resistance. Stellite 12 has a density of 8.6 g/cm³ (0.311 lb/in³), heavier than 63% of cobalt-chrome alloy grades. It melts at 1,280°C (2,336 °F). Stellite 12 has a yield strength of 650 MPa (94.3 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 77% of cobalt-chrome alloy grades. Elongation at break is 1% and the elastic modulus is 230 GPa (33.4 Msi).
What is Stellite 12 used for?
- valve components
- shear blades
- hot forming dies
Stellite 12 properties
Typical room-temperature values; bars are the position among cobalt-chrome alloy grades.
Physical3
Stellite 12 has a density of 8.6 g/cm³ (0.311 lb/in³), heavier than 63% of cobalt-chrome alloy grades. It melts at 1,280°C (2,336 °F).
Mechanical14
Stellite 12 has a yield strength of 650 MPa (94.3 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 77% of cobalt-chrome alloy grades. Elongation at break is 1% and the elastic modulus is 230 GPa (33.4 Msi).
Thermal6
Stellite 12 is rated for continuous service to 800°C (1,472 °F). It conducts heat at 14.5 W/m·K (8.38 BTU/hr·ft·°F), better than 64% of cobalt-chrome alloy grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical3
Stellite 12 conducts electricity at 2 % IACS, better than 79% 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 12 takes about 150 MJ of energy and emits 13 kg of CO₂ — less than 59% of cobalt-chrome alloy grades. Typical recycled content is 25%.
Manufacturability8
Stellite 12's machinability is not recommended (8/100, worse than 64% of cobalt-chrome alloy grades); weldability fair (35/100); formability not recommended (3/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the cobalt-chrome alloy family
Yield strength against density for every cobalt-chrome alloy grade FabDigit runs. Stellite 12 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Stellite 12
Is Stellite 12 easy to machine?
Effectively non-machinable in the hardened state — finish by CBN/SiC grinding, lapping or EDM; only very light carbide turning at low speed with rigid setups.
Can Stellite 12 be welded?
Deposit by PTA, GTAW, laser or covered electrode with 300–500 °C preheat, controlled interpass temperature and slow cooling to avoid transverse cracking; expect fine check cracks in thick single-pass beads.
Can Stellite 12 be formed, bent or molded?
No cold or hot forming — shape by casting, powder consolidation (HIP) or near-net weld/laser deposition and then grind.
Stellite 12 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 |
|---|---|---|
| CrAWS A5.21 CoCr-B range | 26 – 32 | 30 |
| W | 7 – 9.5 | 8.5 |
| Cprimary carbide former | 1 – 1.7 | 1.45 |
| Ni | ≤ 3 | 1 |
| Femax (undiluted deposit) | ≤ 3 | 1.5 |
| Si | ≤ 2 | 1 |
| Mn | ≤ 2 | 0.8 |
| Mo | ≤ 1 | 0.3 |
| Cobalance, nominally ~55% | balance |
What surface finishes work on Stellite 12?
Ground and lapped sealing faces polish to a mirror finish; no anodizing or plating is used, and the alloy is normally left bare as the corrosion/wear surface.
Equivalent designations
Standards and trade names that resolve to Cobalt-Chrome Alloy Stellite 12 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- R30012
How much does Stellite 12 cost?
Stellite 12 is a high-cost cobalt-chrome alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Stellite 12 — frequently asked
What is Stellite 12 used for?
Stellite 12 is typically used for valve components, shear blades and hot forming dies. In short: balanced hardness and toughness; mid-carbide Stellite grade; overlay or cast forms.
What is the yield strength of Stellite 12?
Stellite 12 has a typical yield strength of 650 MPa (94.3 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 77% of cobalt-chrome alloy grades. Strength varies by condition: see the 3 listed tempers.
Is Stellite 12 easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 64% of cobalt-chrome alloy grades). Effectively non-machinable in the hardened state — finish by CBN/SiC grinding, lapping or EDM; only very light carbide turning at low speed with rigid setups.
Can Stellite 12 be welded?
With care — weldability is rated fair (35/100). Deposit by PTA, GTAW, laser or covered electrode with 300–500 °C preheat, controlled interpass temperature and slow cooling to avoid transverse cracking; expect fine check cracks in thick single-pass beads.
What surface finishes work on Stellite 12?
Ground and lapped sealing faces polish to a mirror finish; no anodizing or plating is used, and the alloy is normally left bare as the corrosion/wear surface.
Can Stellite 12 be formed, bent or molded?
No cold or hot forming — shape by casting, powder consolidation (HIP) or near-net weld/laser deposition and then grind.
What is the maximum service temperature of Stellite 12?
Stellite 12 is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Stellite 12 cost?
Stellite 12 is a high-cost cobalt-chrome alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- AWS A5.21/A5.21M — Bare Electrodes and Rods for Surfacing (CoCr-B) — AWS (2011)
- AWS A5.13 — Surfacing Electrodes for SMAW (ECoCr-B) — AWS (2010)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Cobalt wear alloys) — ASM International (1990)
- Stellite 12 alloy data sheet — Kennametal Stellite / Deloro (2022)
- UNS R30012 alloy record — SAE/ASTM UNS (2020)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.