C4
GB YG3 · ISO K01
C4 is the hardest, finest-grain grade in the US straight WC-Co series (YG3), intended for precision finishing at light chip loads.
Reference datasheet — C4 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.
Values for the FG condition
C4 tempers and conditions
C4 is supplied in 2 conditions, soft to hard. FG is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
FGDefault Fine grain WC-3Co (1.0–1.5 µm), as-sintered/ground | Standard C4/K01 straight carbide for finishing cast iron and non-ferrous alloys and for general wear parts. | 1,200 | 0 | 1,850 HV | 100 W/m·K | |
Ultrafine/submicron WC-3Co (0.4–0.8 µm), YG3X | Pick when maximum hardness and a keen, chip-free edge are needed — micro-tools, PCB drills, precision dies and slitters. | 2,050 HV | 85 W/m·K |
Supply forms, finishes and certifications
Ways C4 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
PVD | C4 substrate with TiN/TiAlN PVD coating | Coating |
What is C4?
C4 is the hardest, finest-grain grade in the US straight WC-Co series (YG3), intended for precision finishing at light chip loads. It is used for fine boring tools, wire drawing dies and finishing inserts, and is stocked as fine-grain (FG), ultrafine (UF) and PVD-coated blanks. Elastic modulus reaches 665 GPa with 100 W/m·K thermal conductivity, but maximum service temperature is about 600 °C and the low binder content makes the grade sensitive to shock and interrupted cuts. C3 or C2 give more toughness at the cost of edge wear resistance. C4 has a density of 15.2 g/cm³ (0.549 lb/in³), heavier than 100% of ceramic grades. It melts at 1,320°C (2,408 °F). C4 has a tensile strength of 1,200 MPa (174 ksi), stronger than 94% of ceramic grades. Elongation at break is 0% and the elastic modulus is 665 GPa (96.5 Msi).
What is C4 used for?
- precision finishing
- wire drawing dies
- fine boring
Advantages
- Stiff — 665 GPa (96.5 Msi), better than 99% of ceramic grades
- Polishes to a fine finish — 92/100, better than 89% of ceramic grades
- Conducts heat well — 100 W/m·K (57.8 BTU/hr·ft·°F), better than 83% of ceramic grades
- Tough — resists crack growth — 8 MPa·√m (7.28 ksi·√in), better than 77% of ceramic grades
Limitations
- Heavy — 15.2 g/cm³ (0.549 lb/in³), worse than 100% of ceramic grades
- High embodied carbon — 30 kg CO₂/kg, worse than 91% of ceramic grades
- Needs corrosion protection — 45/100, worse than 90% of ceramic grades
C4 properties
Typical room-temperature values for C4-FG; bars are the position among ceramic grades.
Physical3
C4 has a density of 15.2 g/cm³ (0.549 lb/in³), heavier than 100% of ceramic grades. It melts at 1,320°C (2,408 °F).
Mechanical13
C4 has a tensile strength of 1,200 MPa (174 ksi), stronger than 94% of ceramic grades. Elongation at break is 0% and the elastic modulus is 665 GPa (96.5 Msi).
Thermal5
C4 is rated for continuous service to 600°C (1,112 °F). It conducts heat at 100 W/m·K (57.8 BTU/hr·ft·°F), better than 83% of ceramic grades. Thermal expansion is 4.5 µm/m·K (2.5 µin/in·°F).
Electrical2
C4 has an electrical resistivity of 1.9×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is fair (45/100), worse than 90% of ceramic grades.
Sustainability4
Producing a kilogram of C4 takes about 400 MJ of energy and emits 30 kg of CO₂ — more than 88% of ceramic grades. Typical recycled content is 30%.
Manufacturability3
C4's machinability is not recommended (3/100, worse than 95% of ceramic grades).
Common Calculations4
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 ceramic family
Yield strength against density for every ceramic grade FabDigit runs. C4 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with C4
Is C4 easy to machine?
Only diamond grinding, wire/sinker EDM, laser or ultrasonic machining — never conventional cutting; grind wet with generous coolant to avoid thermal cracks.
Can C4 be welded?
Not fusion weldable; join by vacuum or induction brazing with Ag-Cu-(Ti/Ni) filler below ~900 °C, using a shim to absorb CTE mismatch with steel.
Can C4 be formed, bent or molded?
Net-shape by pressing or extruding WC-Co powder with binder then vacuum/sinter-HIP at ~1420 °C with ~18–22 % linear shrinkage; no plastic forming after sintering.
C4 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 |
|---|---|---|
| Cobinder phase; defines toughness/hardness balance | 2.5 – 4 | 3 |
| TiC+TaC+NbCstraight grade — cubic carbides only as trace grain-growth inhibitor level | 0 – 0.5 | 0 |
| Cr3C2/VCgrain-growth inhibitor, mainly in the ultrafine variant | 0 – 0.8 | 0.4 |
| WCbalance, ~96 wt %; total C ≈ 5.9 % | balance |
What surface finishes work on C4?
Diamond lapping/polishing to mirror finish; PVD TiN/TiAlN or CVD coatings and micro-blast edge honing are standard for cutting tools.
Equivalent designations
Standards and trade names that resolve to C4 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ISO
- K01
- GB (China)
- YG3
How much does C4 cost?
C4 is a high-cost ceramic ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
C4 — frequently asked
What is C4 used for?
C4 is typically used for precision finishing, wire drawing dies and fine boring. In short: hardest US straight carbide; stiffest grade, 665 GPa; light-cut finishing only.
What is the tensile strength of C4?
C4 has a typical tensile strength of 1,200 MPa (174 ksi) — stronger than 94% of ceramic grades. Strength varies by condition: see the 2 listed tempers.
Is C4 easy to machine?
Not especially — machinability is rated not recommended (3/100, worse than 95% of ceramic grades). Only diamond grinding, wire/sinker EDM, laser or ultrasonic machining — never conventional cutting; grind wet with generous coolant to avoid thermal cracks.
Can C4 be welded?
Not fusion weldable; join by vacuum or induction brazing with Ag-Cu-(Ti/Ni) filler below ~900 °C, using a shim to absorb CTE mismatch with steel.
What surface finishes work on C4?
Diamond lapping/polishing to mirror finish; PVD TiN/TiAlN or CVD coatings and micro-blast edge honing are standard for cutting tools.
Can C4 be formed, bent or molded?
Net-shape by pressing or extruding WC-Co powder with binder then vacuum/sinter-HIP at ~1420 °C with ~18–22 % linear shrinkage; no plastic forming after sintering.
What is the maximum service temperature of C4?
C4 is rated for continuous use to about 600°C (1,112 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does C4 cost?
C4 is a high-cost ceramic ($$$$), 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
- ISO 513 — Classification of hard cutting materials (K01 application group) — ISO (2012)
- ASTM B276 / B406 — Apparent porosity and transverse rupture strength of cemented carbides — ASTM (2020)
- ASM Handbook Vol. 2 — Properties of Cemented Carbides — ASM International (1990)
- Straight-grade WC-Co hardmetal property tables — Kennametal / Sandvik Hard Materials / Zhuzhou Cemented Carbide (2023)
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.