TT7K12 VS
Grade · default condition
GOST TT7K12 (ТТ7К12) · GB YW1 · ISO P40
VS = vacuum sintered, standard medium grain
Use the conventional vacuum liquid-phase sintered blank or insert as the general choice for heavy-duty steel turning and planing.
Values for the VS condition
Other TT7K12 tempers and conditions
TT7K12 is listed in 2 conditions; see the grade overview at TT7K12.
- VS
- SHIP
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
VSDefaultThis page Vacuum sintered, standard medium grain | Use the conventional vacuum liquid-phase sintered blank or insert as the general choice for heavy-duty steel turning and planing. | — | 1,150 | 0.2 | 1,200 HV | 30 W/m·K |
Sinter-HIP | Pick the pressure-assisted sinter-HIP condition with near-zero porosity when maximum transverse rupture strength and chipping life are needed for heavy interrupted cuts and large tool bodies. | — | 1,300 | 0.25 | 1,230 HV | 32 W/m·K |
What is TT7K12 VS?
TT7K12 VS is TT7K12 in the VS grade — use the conventional vacuum liquid-phase sintered blank or insert as the general choice for heavy-duty steel turning and planing. TT7K12 VS has a tensile strength of 1,150 MPa (167 ksi), stronger than 90% of ceramic grades. Elongation at break is 0.2% and the elastic modulus is 520 GPa (75.4 Msi). TT7K12 VS has a density of 13.15 g/cm³ (0.475 lb/in³), heavier than 87% of ceramic grades. It melts at 1,300°C (2,372 °F).
Advantages
- Tough — resists crack growth — 13.5 MPa·√m (12.3 ksi·√in), better than 95% of ceramic grades
- Stiff — 520 GPa (75.4 Msi), better than 81% of ceramic grades
- Ductile — tolerates forming and impact — 0.2%, better than 81% of ceramic grades
Limitations
- Needs corrosion protection — 45/100, worse than 90% of ceramic grades
- Heavy — 13.15 g/cm³ (0.475 lb/in³), worse than 87% of ceramic grades
- High embodied carbon — 28 kg CO₂/kg, worse than 84% of ceramic grades
TT7K12 VS properties
Typical room-temperature values for TT7K12 VS; 14 are specific to this condition. Other listed values are TT7K12 reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical3
TT7K12 VS has a density of 13.15 g/cm³ (0.475 lb/in³), heavier than 87% of ceramic grades. It melts at 1,300°C (2,372 °F).
Mechanical13
TT7K12 VS has a tensile strength of 1,150 MPa (167 ksi), stronger than 90% of ceramic grades. Elongation at break is 0.2% and the elastic modulus is 520 GPa (75.4 Msi).
Thermal5
TT7K12 VS is rated for continuous service to 800°C (1,472 °F). It conducts heat at 30 W/m·K (17.3 BTU/hr·ft·°F), better than 60% of ceramic grades. Thermal expansion is 6.5 µm/m·K (3.61 µin/in·°F).
Electrical1
TT7K12 VS 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 TT7K12 VS takes about 320 MJ of energy and emits 28 kg of CO₂ — more than 78% of ceramic grades. Typical recycled content is 25%.
Manufacturability3
TT7K12 VS'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 TT7K12 VS
Is TT7K12 easy to machine?
Shaping after sintering is limited to diamond wheel grinding, EDM or laser machining; conventional cutting tools cannot be used, and grinding needs generous coolant to avoid thermal cracking.
Can TT7K12 be welded?
Not fusion weldable; braze to steel bodies with silver-copper fillers (Ag-Cu-Zn, BAg-1) by vacuum or induction brazing, controlling the heating rate to limit thermal stress.
Can TT7K12 be formed, bent or molded?
Powder pressing or extrusion followed by vacuum liquid-phase sintering at about 1450 °C; linear shrinkage is roughly 18–20% and compacts must be sized for it.
What surface finishes work on TT7K12?
Diamond lapping and polishing gives a mirror finish; CVD/PVD coatings (TiCN, Al₂O₃, TiAlN) increase wear resistance. Electroplating and anodising are not applicable.
TT7K12 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 | 11 – 13 | 12 |
| TiCTiC + TaC total about 7 % | 3 – 5 | 4 |
| TaCincludes a small amount of NbC | 2 – 4 | 3 |
| WC | balance | — |
TT7K12 VS — frequently asked
What is TT7K12 VS used for?
TT7K12 VS is typically used for heavy roughing of steel/forgings, impact-resistant tooling and mining and construction tools. In short: toughest steel-cutting carbide; triple-carbide shock grade; roughing over speed.
What is the tensile strength of TT7K12 VS?
TT7K12 VS has a typical tensile strength of 1,150 MPa (167 ksi) — stronger than 90% of ceramic grades. Strength varies by condition: see the 2 listed tempers.
Is TT7K12 VS easy to machine?
Not especially — machinability is rated not recommended (5/100, worse than 59% of ceramic grades). Shaping after sintering is limited to diamond wheel grinding, EDM or laser machining; conventional cutting tools cannot be used, and grinding needs generous coolant to avoid thermal cracking.
Can TT7K12 VS be welded?
Not fusion weldable; braze to steel bodies with silver-copper fillers (Ag-Cu-Zn, BAg-1) by vacuum or induction brazing, controlling the heating rate to limit thermal stress.
What surface finishes work on TT7K12 VS?
Diamond lapping and polishing gives a mirror finish; CVD/PVD coatings (TiCN, Al₂O₃, TiAlN) increase wear resistance. Electroplating and anodising are not applicable.
Can TT7K12 VS be formed, bent or molded?
Powder pressing or extrusion followed by vacuum liquid-phase sintering at about 1450 °C; linear shrinkage is roughly 18–20% and compacts must be sized for it.
What is the maximum service temperature of TT7K12 VS?
TT7K12 VS 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.
Sources
- ГОСТ 3882 Сплавы твердые спеченные — марки — Госстандарт (1974)
- ASM Handbook Vol. 2 — Properties of Cemented Carbides — ASM International (1990)
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.