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Cobalt-Chrome Alloy Tribaloy T-800-APS

Finish state

UNS R30800

APS = atmospheric plasma sprayed coating

Lower-cost sprayed coating for milder wear duty; more porosity and lower bond strength than HVOF.

High cost $$$$

Values for the APS condition

Other Tribaloy T-800 tempers and conditions

Tribaloy T-800 is listed in 5 conditions; see the grade overview at Tribaloy T-800.

Compare all 5 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
APSThis page
Atmospheric plasma sprayed coating
Lower-cost sprayed coating for milder wear duty; more porosity and lower bond strength than HVOF.—600.155 HRC0.9 % IACS
Bare cast rod / TIG hardfacing deposit, as welded
Manual repair overlays and small localized hardfacing where PTA equipment is unavailable; requires preheat to limit cracking.4304500.256 HRC1.7 % IACS
ACDefault
Spheroidize annealed
Standard supply condition for valve seats, bushings and nozzles machined to net shape by grinding.4805000.358 HRC1.7 % IACS
Laser cladding deposit, as clad
Choose for low-dilution, fine-Laves-phase coatings with minimal HAZ and tight dimensional control.5305500.360 HRC1.7 % IACS
Hot isostatic pressed
Use when a fully dense, fine and uniform Laves-phase structure with slightly better toughness than casting is required.5606000.557 HRC1.8 % IACS

What is Tribaloy T-800-APS?

Tribaloy T-800-APS is Tribaloy T-800 supplied in the APS condition — lower-cost sprayed coating for milder wear duty; more porosity and lower bond strength than HVOF. Tribaloy T-800-APS has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 60 MPa (8.7 ksi) — weaker than 77% of cobalt-chrome alloy grades. Elongation at break is 0.1% and the elastic modulus is 120 GPa (17.4 Msi). Tribaloy T-800-APS has a density of 8 g/cm³ (0.289 lb/in³), lighter than 100% of cobalt-chrome alloy grades. It melts at 1,250°C (2,282 °F). AC is the default condition FabDigit quotes; APS is available on request or by drawing note.

Limitations

  • Low stiffness — 120 GPa (17.4 Msi), worse than 100% of cobalt-chrome alloy grades
  • Limited ductility — 0.1%, worse than 100% of cobalt-chrome alloy grades
  • Low fracture toughness — 4 MPa·√m (3.64 ksi·√in), worse than 100% of cobalt-chrome alloy grades
  • Poor heat conductor — 6 W/m·K (3.47 BTU/hr·ft·°F), worse than 100% of cobalt-chrome alloy grades
  • Low electrical conductivity — 0.9 % IACS, worse than 100% of cobalt-chrome alloy grades

Tribaloy T-800-APS properties

Typical room-temperature values for Tribaloy T-800-APS; 20 are specific to this condition. Other listed values are Tribaloy T-800 reference data and may not represent this condition. Bars are the position among cobalt-chrome alloy grades.

Physical3

Tribaloy T-800-APS has a density of 8 g/cm³ (0.289 lb/in³), lighter than 100% of cobalt-chrome alloy grades. It melts at 1,250°C (2,282 °F).

Density8 g/cm³0.29 lb/in³
Melting Point (Solidus)1,250°C2,282 °F
Liquidus Temperature1,320°C2,408 °F

Mechanical15

Tribaloy T-800-APS has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 60 MPa (8.7 ksi) — weaker than 77% of cobalt-chrome alloy grades. Elongation at break is 0.1% and the elastic modulus is 120 GPa (17.4 Msi).

Elastic (Young's) Modulus120 GPa17.4 Msi
Shear Modulus87 GPa12.6 Msi
Bulk Modulus180 GPa26.1 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)60 MPa8.7 ksi
Yield Strength (0.2% offset)480 MPa69.6 ksi
Elongation at Break0.1%
Reduction in Area0%
Compressive Strength900 MPa131 ksi
Shear Strength150 MPa21.8 ksi
Fatigue Strength (Endurance Limit)80 MPa11.6 ksi
Fracture Toughness (K_IC)4 MPa·√m3.6 ksi·√in
Charpy V-Notch Impact (RT)1 J0.74 ft·lbf
Hardness, Rockwell C55 HRC
Hardness, Vickers600 HV

Thermal5

Tribaloy T-800-APS is rated for continuous service to 700°C (1,292 °F). It conducts heat at 6 W/m·K (3.47 BTU/hr·ft·°F), worse than 100% of cobalt-chrome alloy grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).

Thermal Conductivity6 W/m·K3.5 BTU/hr·ft·°F
Specific Heat Capacity420 J/kg·K0.1 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)12 µm/m·K6.7 µin/in·°F
Max Service Temperature (continuous)700°C1,292 °F
Min Service Temperature-196°C-321 °F

Electrical3

Tribaloy T-800-APS conducts electricity at 0.9 % IACS, worse than 100% of cobalt-chrome alloy grades.

Electrical Conductivity0.9 % IACS
Electrical Resistivity1.9×10⁻⁶ Ω·m74.8 µΩ·in
Magnetic Responseweakly magnetic — Co-Mo-Si matrix plus Laves phase gives low but measurable permeability

Chemical & Environmental3

Corrosion resistance is good (62/100), worse than 86% of cobalt-chrome alloy grades.

Galvanic Potential (seawater, vs SCE)-0.25 V
Corrosion ResistanceGood62/100
Chemical Resistance SummaryVery good resistance to reducing acids, chlorides and hot brines thanks to ~28 % Mo and 17.5 % Cr; resists cavitation and erosion-corrosion; attacked by strong oxidizing acids (hot HNO3) and molten salts.

Sustainability4

Producing a kilogram of Tribaloy T-800-APS takes about 170 MJ of energy and emits 16 kg of CO₂ — more than 63% of cobalt-chrome alloy grades. Typical recycled content is 25%.

Embodied Energy (primary production)170 MJ/kg73,087 BTU/lb
Embodied Carbon (primary production)16 kg CO₂/kg
Embodied Water400 L/kg47.9 gal/lb
Typical Recycled Content25%

Manufacturability7

Tribaloy T-800-APS's machinability is not recommended (4/100, worse than 95% of cobalt-chrome alloy grades); weldability not recommended (5/100); formability not recommended (1/100).

MachinabilityNot recommended4/100
Machinability Rating (AISI 1212 = 100 %)3%
WeldabilityNot recommended5/100
Formability (cold)Not recommended1/100
CastabilityGood60/100
Brazeability / SolderabilityFair45/100
PolishabilityVery good80/100

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with Tribaloy T-800-APS

Is Tribaloy T-800 easy to machine?

Not conventionally machinable — finish by grinding (CBN/diamond, SiC for roughing), EDM or lapping; leave 0.3–0.6 mm grind stock on overlays.

Can Tribaloy T-800 be welded?

Deposit only as hardfacing (PTA/GTAW/laser) with 200–400 °C preheat, slow cooling and thin passes; heavy single-pass layers crack readily and it is not a structural weld metal.

Can Tribaloy T-800 be formed, bent or molded?

Zero cold formability — parts are net-shape cast, HIP-consolidated or clad; all shaping must be done in the liquid or powder state.

What surface finishes work on Tribaloy T-800?

Grinding/lapping yields a hard, glossy sealing surface with excellent scratch and galling resistance; no plating or anodizing needed, and coatings are usually left as-ground.

Tribaloy T-800 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.

ElementSpec limit (wt %)Nominal
Moforms CoMoSi Laves phase26 – 3028.5
Cr16 – 1917.5
SiLaves-phase former3 – 3.83.4
C≤ 0.080.05
Ni≤ 1.50.5
Fe≤ 1.50.5
Cobalance, nominally ~48-52 %balance—

Tribaloy T-800-APS — frequently asked

What is Tribaloy T-800-APS used for?

Tribaloy T-800-APS is typically used for severe abrasive wear surfaces, valve trim, hot extrusion tooling and thermal spray coatings. In short: hardest Tribaloy grade; laves-phase abrasion resistance; grind-only, very low ductility.

What is the yield strength of Tribaloy T-800-APS?

Tribaloy T-800-APS has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 60 MPa (8.7 ksi) — weaker than 77% of cobalt-chrome alloy grades. Strength varies by condition: see the 5 listed tempers.

Is Tribaloy T-800-APS easy to machine?

Not especially — machinability is rated not recommended (4/100, worse than 95% of cobalt-chrome alloy grades). Not conventionally machinable — finish by grinding (CBN/diamond, SiC for roughing), EDM or lapping; leave 0.3–0.6 mm grind stock on overlays.

Can Tribaloy T-800-APS be welded?

Not readily — weldability is rated not recommended (5/100). Deposit only as hardfacing (PTA/GTAW/laser) with 200–400 °C preheat, slow cooling and thin passes; heavy single-pass layers crack readily and it is not a structural weld metal.

What surface finishes work on Tribaloy T-800-APS?

Grinding/lapping yields a hard, glossy sealing surface with excellent scratch and galling resistance; no plating or anodizing needed, and coatings are usually left as-ground.

Can Tribaloy T-800-APS be formed, bent or molded?

Zero cold formability — parts are net-shape cast, HIP-consolidated or clad; all shaping must be done in the liquid or powder state.

What is the maximum service temperature of Tribaloy T-800-APS?

Tribaloy T-800-APS is rated for continuous use to about 700°C (1,292 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between Tribaloy T-800-AC and Tribaloy T-800-HIP?

AC is the default condition — standard supply condition for valve seats, bushings and nozzles machined to net shape by grinding. HIP: use when a fully dense, fine and uniform Laves-phase structure with slightly better toughness than casting is required. Yield strength is 480 MPa in AC versus 560 MPa in HIP.

Sources

  1. Tribaloy T-800 alloy data sheet — Kennametal Stellite / Deloro Wear Solutions (2021)
  2. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (cobalt alloys) — ASM International (1990)
  3. UNS R30800 alloy designation (Metals & Alloys in the Unified Numbering System) — SAE/ASTM (2017)
  4. ASM Handbook Vol. 5A — Thermal Spray Technology (Co-Mo-Si wear coatings) — ASM International (2013)

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.