ZrC SPS
Grade
SPS = spark-plasma (field-assisted) sintered, ≥98 % dense fine grain
Pick when maximum hardness, strength and near-full density in a fine-grained body are required (small discs, research UHTC parts).
Values for the SPS condition
Other ZrC tempers and conditions
ZrC is listed in 3 conditions; see the grade overview at ZrC.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Pressureless sintered ZrC, 88–95 % theoretical density | Choose for larger or complex shapes where cost and near-net forming matter more than peak strength; residual porosity lowers strength and conductivity. | — | — | — | 1,700 HV | 16 W/m·K |
HPDefault Hot-pressed ZrC, ≥95 % theoretical density | General-purpose dense ZrC billets and plates for UHTC structures, electrodes and tooling inserts. | — | — | — | 2,200 HV | 22 W/m·K |
SPSThis page Spark-plasma (field-assisted) sintered, ≥98 % dense fine grain | Pick when maximum hardness, strength and near-full density in a fine-grained body are required (small discs, research UHTC parts). | — | — | — | 2,500 HV | 25 W/m·K |
What is ZrC SPS?
ZrC SPS is ZrC in the SPS grade — pick when maximum hardness, strength and near-full density in a fine-grained body are required (small discs, research UHTC parts). The elastic modulus is 430 GPa (62.4 Msi). ZrC SPS has a density of 6.6 g/cm³ (0.238 lb/in³), heavier than 70% of ceramic grades. It melts at 3,420°C (6,188 °F). HP is the default condition FabDigit quotes; SPS is available on request or by drawing note.
Advantages
- High service temperature — 1,900°C (3,452 °F), better than 94% of ceramic grades
Limitations
- Needs corrosion protection — 55/100, worse than 77% of ceramic grades
ZrC SPS properties
Typical room-temperature values for ZrC SPS; 12 are specific to this condition. Other listed values are ZrC reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical3
ZrC SPS has a density of 6.6 g/cm³ (0.238 lb/in³), heavier than 70% of ceramic grades. It melts at 3,420°C (6,188 °F).
Mechanical10
The elastic modulus is 430 GPa (62.4 Msi).
Thermal5
ZrC SPS is rated for continuous service to 1,900°C (3,452 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), better than 55% of ceramic grades. Thermal expansion is 6.7 µm/m·K (3.72 µin/in·°F).
Electrical2
ZrC SPS has an electrical resistivity of 4×10⁻⁷ Ω·m.
Chemical & Environmental2
Corrosion resistance is good (55/100), worse than 77% of ceramic grades.
Sustainability3
Producing a kilogram of ZrC SPS takes about 250 MJ of energy and emits 22 kg of CO₂ — more than 67% of ceramic grades. Typical recycled content is 0%.
Manufacturability3
ZrC SPS's machinability is not recommended (4/100, worse than 85% of ceramic grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ZrC SPS
Is ZrC easy to machine?
Green or pre-sintered bodies can be shaped conventionally; fired ZrC needs diamond grinding, lapping or EDM (it is electrically conductive, so wire/sinker EDM works well).
Can ZrC be welded?
Not weldable; join by active brazing (Ti/Zr-bearing filler), diffusion bonding, or co-sintering with metal or carbide interlayers.
Can ZrC be formed, bent or molded?
Formed by uniaxial/cold-isostatic pressing then hot pressing, SPS or pressureless sintering above 2100 °C; sintering aids (C, B4C, SiC, MoSi2) and low-oxygen powder are needed for density.
What surface finishes work on ZrC?
Diamond polish to a metallic grey mirror; for air service above ~500 °C apply SiC, ZrB2-SiC or iridium overlays, since bare ZrC oxidises to porous ZrO2.
ZrC 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 |
|---|---|---|
| Ccombined carbon; ZrCx typically x = 0.93–1.00 | 10.8 – 11.7 | 11.6 |
| free Cresidual free carbon from carbothermal reduction | 0 – 0.6 | 0.3 |
| Ooxygen on powder surfaces; degrades sintering and conductivity | 0 – 0.8 | 0.3 |
| N | 0 – 0.3 | 0.1 |
| Hfnatural Hf accompanies Zr unless nuclear-grade (Hf < 100 ppm) | 0.5 – 2.5 | 1.5 |
| Fe | 0 – 0.2 | 0.05 |
| Zr | balance | — |
ZrC SPS — frequently asked
What is ZrC SPS used for?
ZrC SPS is typically used for nuclear TRISO fuel coatings, UHTC composites, cutting tool inserts, wear-resistant coatings and rocket nozzle liners. In short: 1800 °C inert-service carbide; conductive, EDM-friendly ceramic; needs oxidation coating.
Is ZrC SPS easy to machine?
Not especially — machinability is rated not recommended (4/100, worse than 85% of ceramic grades). Green or pre-sintered bodies can be shaped conventionally; fired ZrC needs diamond grinding, lapping or EDM (it is electrically conductive, so wire/sinker EDM works well).
Can ZrC SPS be welded?
Not weldable; join by active brazing (Ti/Zr-bearing filler), diffusion bonding, or co-sintering with metal or carbide interlayers.
What surface finishes work on ZrC SPS?
Diamond polish to a metallic grey mirror; for air service above ~500 °C apply SiC, ZrB2-SiC or iridium overlays, since bare ZrC oxidises to porous ZrO2.
Can ZrC SPS be formed, bent or molded?
Formed by uniaxial/cold-isostatic pressing then hot pressing, SPS or pressureless sintering above 2100 °C; sintering aids (C, B4C, SiC, MoSi2) and low-oxygen powder are needed for density.
What is the maximum service temperature of ZrC SPS?
ZrC SPS is rated for continuous use to about 1,900°C (3,452 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Handbook of Refractory Carbides and Nitrides — Noyes / William Andrew (H.O. Pierson) (1996)
- Engineered Materials Handbook Vol. 4: Ceramics and Glasses — ASM International (1991)
- Properties of zirconium carbide for nuclear fuel applications (review) — Journal of Nuclear Materials (2013)
- Technical ZrC powder and hot-pressed part datasheets — Chinese advanced-ceramic powder suppliers (2024)
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.