YG8 MG
Grade · default condition
AISI/SAE C1 · ISO K20
MG = medium grain (1.5–3 µm WC), standard YG8, sinter-HIP
Default balanced grade for general roughing, dies and wear parts (ISO K20–K30).
Values for the MG condition
Other YG8 tempers and conditions
YG8 is listed in 3 conditions; see the grade overview at YG8.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
MGDefaultThis page Medium grain (1.5–3 µm WC), standard YG8, sinter-HIP | Default balanced grade for general roughing, dies and wear parts (ISO K20–K30). | — | 1,200 | 0.1 | 1,350 HV | 75 W/m·K |
Coarse grain (3–6 µm WC), YG8C, maximum toughness | Pick for heavy impact and thermal shock: mining/rock bits, snowplough blades, hot rolls. | — | 1,300 | 0.15 | 1,180 HV | 85 W/m·K |
Normalized | Pick when a sharp, wear-resistant edge is needed at 8 % Co toughness — micro-drills, PCB tooling, precision punches. | — | 1,500 | 0.1 | 1,550 HV | 68 W/m·K |
What is YG8 MG?
YG8 MG is YG8 in the MG grade — default balanced grade for general roughing, dies and wear parts (ISO K20–K30). YG8 MG has a tensile strength of 1,200 MPa (174 ksi), stronger than 94% of ceramic grades. Elongation at break is 0.1% and the elastic modulus is 600 GPa (87 Msi). YG8 MG has a density of 14.7 g/cm³ (0.531 lb/in³), heavier than 93% of ceramic grades. It melts at 1,320°C (2,408 °F).
Advantages
- Tough — resists crack growth — 14 MPa·√m (12.7 ksi·√in), better than 96% of ceramic grades
- Stiff — 600 GPa (87 Msi), better than 91% of ceramic grades
- Polishes to a fine finish — 90/100, better than 78% of ceramic grades
Limitations
- Heavy — 14.7 g/cm³ (0.531 lb/in³), worse than 93% of ceramic grades
- Needs corrosion protection — 45/100, worse than 90% of ceramic grades
YG8 MG properties
Typical room-temperature values for YG8 MG; 13 are specific to this condition. Other listed values are YG8 reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical3
YG8 MG has a density of 14.7 g/cm³ (0.531 lb/in³), heavier than 93% of ceramic grades. It melts at 1,320°C (2,408 °F).
Mechanical13
YG8 MG has a tensile strength of 1,200 MPa (174 ksi), stronger than 94% of ceramic grades. Elongation at break is 0.1% and the elastic modulus is 600 GPa (87 Msi).
Thermal5
YG8 MG is rated for continuous service to 600°C (1,112 °F). It conducts heat at 75 W/m·K (43.3 BTU/hr·ft·°F), better than 73% of ceramic grades. Thermal expansion is 4.8 µm/m·K (2.67 µin/in·°F).
Electrical2
YG8 MG has an electrical resistivity of 2×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is fair (45/100), worse than 90% of ceramic grades.
Sustainability4
Producing a kilogram of YG8 MG takes about 180 MJ of energy and emits 12 kg of CO₂ — more than 60% of ceramic grades. Typical recycled content is 30%.
Manufacturability3
YG8 MG's machinability is not recommended (5/100, worse than 59% of ceramic grades).
Common Calculations4
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with YG8 MG
Is YG8 easy to machine?
Only diamond grinding, wire/sinker EDM (it is electrically conductive) or laser; green-state pressed blanks can be soft-machined before sintering.
Can YG8 be welded?
Not fusion weldable — join by vacuum/induction brazing with Ag-Cu-Zn or Cu-Mn fillers, using a ductile shim to absorb the CTE mismatch with steel.
Can YG8 be formed, bent or molded?
Made by pressing or extruding WC+Co powder and liquid-phase sinter-HIP at ~1400–1450 °C; allow ~18–20 % linear shrinkage and never plastically form the sintered part.
What surface finishes work on YG8?
Diamond lapping/polishing gives mirror finishes; PVD TiN/TiAlN or CVD coatings, and micro-blasting for edge prep, are the usual surface treatments.
YG8 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 |
|---|---|---|
| Cometallic binder phase | 7.5 – 8.5 | 8 |
| TaC+NbCoptional grain-growth inhibitor in some producers' YG8 | 0 – 0.5 | 0.2 |
| Ctotal carbon, must stay in two-phase window (no eta phase, no free graphite) | 5.5 – 5.9 | 5.7 |
| WCbalance, tungsten carbide hard phase | balance | — |
YG8 MG — frequently asked
What is YG8 MG used for?
YG8 MG is typically used for roughing cast iron, mining/rock tools, stamping dies and wear liners. In short: toughest straight WC-Co grade; roughing and impact duty; lower hardness than YG6.
What is the tensile strength of YG8 MG?
YG8 MG has a typical tensile strength of 1,200 MPa (174 ksi) — stronger than 94% of ceramic grades. Strength varies by condition: see the 3 listed tempers.
Is YG8 MG easy to machine?
Not especially — machinability is rated not recommended (5/100, worse than 59% of ceramic grades). Only diamond grinding, wire/sinker EDM (it is electrically conductive) or laser; green-state pressed blanks can be soft-machined before sintering.
Can YG8 MG be welded?
Not fusion weldable — join by vacuum/induction brazing with Ag-Cu-Zn or Cu-Mn fillers, using a ductile shim to absorb the CTE mismatch with steel.
What surface finishes work on YG8 MG?
Diamond lapping/polishing gives mirror finishes; PVD TiN/TiAlN or CVD coatings, and micro-blasting for edge prep, are the usual surface treatments.
Can YG8 MG be formed, bent or molded?
Made by pressing or extruding WC+Co powder and liquid-phase sinter-HIP at ~1400–1450 °C; allow ~18–20 % linear shrinkage and never plastically form the sintered part.
What is the maximum service temperature of YG8 MG?
YG8 MG 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.
Sources
- ISO 513 Classification and application of hard cutting materials — ISO (2012)
- ISO 28079 Hardmetals — Palmqvist toughness test — ISO (2009)
- ASM Engineered Materials Handbook Vol.4 — Ceramics and Glasses / Cemented Carbides — ASM International (1991)
- Cemented carbide grade data (WC-8Co K20/K30 class) — Zhuzhou Cemented Carbide / Sandvik Hard Materials (2023)
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.