Cobalt-Chrome Alloy Stellite 6 As Welded
Finish state
UNS R30006 · also CoCrW Stellite
Pick for on-part hardfacing of valve seats, shafts and edges; hardness of the first layer drops with substrate dilution, so deposit two or more layers.
Values for the As Welded condition
Other Stellite 6 tempers and conditions
Stellite 6 is listed in 5 conditions; see the grade overview at Stellite 6.
- As Welded
- As Cast
- Hot Worked
- HIP
- AM As-Built
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As WeldedThis page GTAW/PTA/oxy-acetylene hardfacing deposit | Pick for on-part hardfacing of valve seats, shafts and edges; hardness of the first layer drops with substrate dilution, so deposit two or more layers. | 520 | 800 | 1 | 41 HRC | 1.9 % IACS |
As CastDefault chill/investment cast bar, seat ring or casting | Default supply form for valve trim, seat rings and cast wear parts; maximum carbide content, lowest ductility. | 541 | 834 | 1 | 40 HRC | — |
hot rolled/forged wrought bar, plate or sheet | Choose when some ductility and toughness are needed alongside wear resistance (bushings, blades, wear plate); carbides are broken up and aligned. | 620 | 1,000 | 9 | 38 HRC | — |
Hot isostatic pressed | Choose for near-net-shape parts needing uniform fine carbides, higher strength and better toughness than cast Stellite 6. | 680 | 1,000 | 4 | 42 HRC | 1.9 % IACS |
laser powder-bed / laser cladding as-deposited | Pick for printed or laser-clad wear parts; rapid solidification gives fine dendrites, higher hardness and strength but residual stress and anisotropy. | 720 | 1,100 | 4 | 45 HRC | 1.8 % IACS |
What is Stellite 6 As Welded?
Stellite 6 As Welded is Stellite 6 supplied in the As Welded condition — pick for on-part hardfacing of valve seats, shafts and edges; hardness of the first layer drops with substrate dilution, so deposit two or more layers. Stellite 6 As Welded has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 800 MPa (116 ksi) — weaker than 54% of cobalt-chrome alloy grades. Elongation at break is 1% and the elastic modulus is 210 GPa (30.5 Msi). Stellite 6 As Welded has a density of 8.44 g/cm³ (0.305 lb/in³), lighter than 52% of cobalt-chrome alloy grades. It melts at 1,285°C (2,345 °F). As Cast is the default condition FabDigit quotes; As Welded is available on request or by drawing note.
Advantages
- Readily welded — 55/100, better than 80% of cobalt-chrome alloy grades
Limitations
- Needs corrosion protection — 66/100, worse than 82% of cobalt-chrome alloy grades
Stellite 6 As Welded properties
Typical room-temperature values for Stellite 6 As Welded; 21 are specific to this condition. Other listed values are Stellite 6 reference data and may not represent this condition. Bars are the position among cobalt-chrome alloy grades.
Physical3
Stellite 6 As Welded has a density of 8.44 g/cm³ (0.305 lb/in³), lighter than 52% of cobalt-chrome alloy grades. It melts at 1,285°C (2,345 °F).
Mechanical13
Stellite 6 As Welded has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 800 MPa (116 ksi) — weaker than 54% of cobalt-chrome alloy grades. Elongation at break is 1% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal5
Stellite 6 As Welded 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 12.5 µm/m·K (6.94 µin/in·°F).
Electrical3
Stellite 6 As Welded conducts electricity at 1.9 % IACS, worse than 52% of cobalt-chrome alloy grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), worse than 82% of cobalt-chrome alloy grades.
Sustainability4
Producing a kilogram of Stellite 6 As Welded takes about 150 MJ of energy and emits 13 kg of CO₂ — less than 59% of cobalt-chrome alloy grades. Typical recycled content is 30%.
Manufacturability8
Stellite 6 As Welded's machinability is not recommended (6/100, worse than 75% of cobalt-chrome alloy grades); weldability good (55/100); formability not recommended (2/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Stellite 6 As Welded
Is Stellite 6 easy to machine?
Treat as a grinding/EDM material — cast Stellite 6 at 40 HRC work-hardens and abrades tools; if turning, use negative-rake CBN or C2 carbide, rigid setup, low speed (10–25 m/min), heavy feed and flood coolant.
Can Stellite 6 be welded?
Deposit by GTAW, PTA, oxy-acetylene or laser cladding with 200–350 °C preheat and slow cooling; expect fine transverse check cracks (usually acceptable), and use 2+ layers or a buffer layer on carbon/low-alloy steel to limit iron dilution.
Can Stellite 6 be formed, bent or molded?
No practical cold forming — parts are cast to near-net shape, PM/HIP consolidated, printed, or hot worked above ~1100 °C in the wrought grade.
What surface finishes work on Stellite 6?
Finish by wet grinding, lapping or superfinishing for valve-seat flatness; do not anodize — surfaces are used bare or lightly passivated, and the alloy takes a mirror polish that improves erosion/sealing life.
Stellite 6 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 |
|---|---|---|
| Cr | 27 – 32 | 29 |
| W | 3.5 – 5.5 | 4.5 |
| Cforms Cr7C3 / M23C6 and W-rich carbides | 0.9 – 1.4 | 1.1 |
| Ni | ≤ 3 | 1 |
| Fe | ≤ 3 | 1.5 |
| Si | ≤ 2 | 1.1 |
| Mn | ≤ 2 | 1 |
| Mo | ≤ 1.5 | 0.5 |
| Cobalance, ~57–60 % | balance | — |
Stellite 6 As Welded — frequently asked
What is Stellite 6 As Welded used for?
Stellite 6 As Welded is typically used for valve seats and valve trim, hardfacing rods and welding wire, pump sleeves and wear rings, extruder and screw flight overlays, cutting knives and saw teeth and bearing bushings and thrust washers. In short: hardfacing cobalt alloy.
What is the yield strength of Stellite 6 As Welded?
Stellite 6 As Welded has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 800 MPa (116 ksi) — weaker than 54% of cobalt-chrome alloy grades. Strength varies by condition: see the 5 listed tempers.
Is Stellite 6 As Welded easy to machine?
Not especially — machinability is rated not recommended (6/100, worse than 75% of cobalt-chrome alloy grades). Treat as a grinding/EDM material — cast Stellite 6 at 40 HRC work-hardens and abrades tools; if turning, use negative-rake CBN or C2 carbide, rigid setup, low speed (10–25 m/min), heavy feed and flood coolant.
Can Stellite 6 As Welded be welded?
Yes — weldability is rated good (55/100). Deposit by GTAW, PTA, oxy-acetylene or laser cladding with 200–350 °C preheat and slow cooling; expect fine transverse check cracks (usually acceptable), and use 2+ layers or a buffer layer on carbon/low-alloy steel to limit iron dilution.
What surface finishes work on Stellite 6 As Welded?
Finish by wet grinding, lapping or superfinishing for valve-seat flatness; do not anodize — surfaces are used bare or lightly passivated, and the alloy takes a mirror polish that improves erosion/sealing life.
Can Stellite 6 As Welded be formed, bent or molded?
No practical cold forming — parts are cast to near-net shape, PM/HIP consolidated, printed, or hot worked above ~1100 °C in the wrought grade.
What is the maximum service temperature of Stellite 6 As Welded?
Stellite 6 As Welded 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 6 As Cast and Stellite 6-HIP?
As Cast is the default condition — default supply form for valve trim, seat rings and cast wear parts; maximum carbide content, lowest ductility. HIP: choose for near-net-shape parts needing uniform fine carbides, higher strength and better toughness than cast Stellite 6. Yield strength is 541 MPa in As Cast versus 680 MPa in HIP.
Sources
- Stellite 6 Alloy Technical Data — Kennametal Stellite (Deloro) (2021)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Cobalt alloys) — ASM International (1990)
- AWS A5.21 / A5.13 — Bare and covered hardfacing electrodes (ERCCoCr-A, RCoCr-A) — AWS (2021)
- ASTM A560 / UNS R30006 cobalt-chromium-tungsten alloy castings — ASTM (2019)
- ASM Handbook Vol.19 — Fatigue and Fracture (hardfacing alloys) — ASM International (1996)
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.