ZrB2-SiC
ZrB2-SiC is an ultra-high-temperature ceramic composite of zirconium diboride with 10–30% SiC particulate or whisker additions (ZS10 to ZS30), consolidated by hot pressing, spark plasma sintering or pressureless sintering with B4C/C/MoSi2 aids.
Reference datasheet — ZrB2-SiC 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 ZS20-HP condition
ZrB2-SiC grades and fills
ZrB2-SiC is supplied in 7 conditions, soft to hard. ZS20-HP is the default FabDigit quotes; the values on this page are for it.
Compare all 7 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Cf/ZrB2-SiC | Choose for large, damage-tolerant hot structures where pseudo-ductile, non-catastrophic failure is mandatory. | 180 | 0.5 | ||
ZrB2-SiC with graphite/carbon-black addition | Select where thermal-shock resistance and machinability outrank absolute bend strength (nozzles, electrodes, crucibles). | 190 | 0.1 | ||
ZrB2 + 10 vol% SiC, hot pressed | Choose when maximum thermal/electrical conductivity and stiffness matter more than oxidation life above 1500 °C. | 280 | 0.12 | ||
ZrB2-SiC with 10–20 vol% MoSi2 | Use when long isothermal oxidation life at 1400–1600 °C is the driver; MoSi2 also aids pressureless densification. | 300 | 0.14 | ||
ZrB2 + 30 vol% SiC, hot pressed | Pick when oxidation life and room-temperature strength dominate and lower conductivity is acceptable. | 350 | 0.16 | ||
SiC-whisker / chopped-fibre toughened ZrB2-SiC | Pick when a ~30 % gain in fracture toughness and crack-deflection behaviour is needed in a monolithic-like body. | 380 | 0.18 | ||
ZS20-HPDefault ZrB2 + 20 vol% SiC, hot pressed | The industry/NASA baseline UHTC: best balance of strength, oxidation resistance and conductivity for hypersonic leading edges. |
Supply forms, finishes and certifications
Ways ZrB2-SiC is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
ZS20-PS | Pressureless sintered with B4C/C or MoSi2 aids | Supply option |
ZS20-SPS | ZrB2-20SiC, spark plasma sintered | Supply option |
What is ZrB2-SiC?
ZrB2-SiC is an ultra-high-temperature ceramic composite of zirconium diboride with 10–30% SiC particulate or whisker additions (ZS10 to ZS30), consolidated by hot pressing, spark plasma sintering or pressureless sintering with B4C/C/MoSi2 aids. Its 490 GPa modulus, 78 W/m·K conductivity, corrosion-resistance score of 75 and 1600 °C rated service — with short-duration leading-edge surface temperatures above 2000 °C — target hypersonic and re-entry hardware. Density is high at 5.5 g/cm³ and machinability is rated 8, so near-net sintering is preferred, though the material's electrical conductivity at least allows EDM. Oxidation or emissivity coatings are usually applied for repeated cycles. ZrB2-SiC has a density of 5.5 g/cm³ (0.199 lb/in³), heavier than 94% of composite grades. ZrB2-SiC has a tensile strength of 320 MPa (46.4 ksi), stronger than 57% of composite grades. The elastic modulus is 490 GPa (71.1 Msi).
What is ZrB2-SiC used for?
- hypersonic vehicle nose caps and leading edges
- rocket nozzle inserts
- plasma-facing components
- re-entry thermal protection
Advantages
- High service temperature — 1,600°C (2,912 °F), better than 100% of composite grades
- Stiff — 490 GPa (71.1 Msi), better than 97% of composite grades
- Polishes to a fine finish — 80/100, better than 97% of composite grades
- Good UV / weathering resistance — 100/100, better than 93% of composite grades
- Conducts heat well — 78 W/m·K (45.1 BTU/hr·ft·°F), better than 88% of composite grades
Limitations
- Heavy — 5.5 g/cm³ (0.199 lb/in³), worse than 94% of composite grades
- Difficult to machine — 8/100, worse than 94% of composite grades
ZrB2-SiC properties
Typical room-temperature values for ZrB2-SiC-ZS20-HP; bars are the position among composite grades.
Physical1
ZrB2-SiC has a density of 5.5 g/cm³ (0.199 lb/in³), heavier than 94% of composite grades.
Mechanical9
ZrB2-SiC has a tensile strength of 320 MPa (46.4 ksi), stronger than 57% of composite grades. The elastic modulus is 490 GPa (71.1 Msi).
Thermal6
ZrB2-SiC is rated for continuous service to 1,600°C (2,912 °F). It conducts heat at 78 W/m·K (45.1 BTU/hr·ft·°F), better than 88% of composite grades. Thermal expansion is 6 µm/m·K (3.33 µin/in·°F).
Electrical2
ZrB2-SiC has an electrical resistivity of 1.5×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (75/100), worse than 55% of composite grades. UV resistance is excellent.
Sustainability3
Producing a kilogram of ZrB2-SiC takes about 300 MJ of energy and emits 22 kg of CO₂ — more than 68% of composite grades. Typical recycled content is 0%.
Manufacturability2
ZrB2-SiC's machinability is not recommended (8/100, worse than 94% of composite 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 composite family
Yield strength against density for every composite grade FabDigit runs. ZrB2-SiC is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ZrB2-SiC
Is ZrB2-SiC easy to machine?
Diamond grinding/lapping only for conventional cutting; because ZrB2-SiC is electrically conductive it can be wire- and sinker-EDM machined, which is the practical route for complex leading-edge geometries.
Can ZrB2-SiC be welded?
Not weldable; joining is by active brazing (Ti/Zr-bearing filler), reaction bonding, or mechanical/co-sintered attachment to metallic or C/C substructures.
Can ZrB2-SiC be formed, bent or molded?
Shaped by hot pressing, spark plasma sintering, or pressureless sintering (with B4C/C/MoSi2 aids) from green bodies made by cold pressing, slip/tape casting or additive-manufactured preforms; near-net shaping is preferred because post-sinter machining is very costly.
ZrB2-SiC 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 |
|---|---|---|
| SiC20 vol% SiC ≈ 11.6 wt% for the baseline ZS20 grade | 5 – 20 | 11.6 |
| B4Coptional sintering aid / oxide scavenger | 0 – 2 | 0.5 |
| Cfree carbon aid; removes ZrO2/B2O3 surface oxides | 0 – 2 | 0.3 |
| ZrO2 + B2O3 impuritiesresidual powder oxides | 0 – 1.5 | 0.5 |
| ZrB2matrix phase, ~88 wt% in ZS20 | balance |
What surface finishes work on ZrB2-SiC?
Diamond lapping/polishing to sub-µm Ra; oxidation-protective or emissivity coatings (SiC CVD, silicide, HfO2-based) are often applied for repeated re-entry cycles.
Equivalent designations
Standards and trade names that resolve to ZrB2-SiC in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Also called
- UHTC
How much does ZrB2-SiC cost?
ZrB2-SiC is a high-cost composite ($$$$), 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.
ZrB2-SiC — frequently asked
What is ZrB2-SiC used for?
ZrB2-SiC is typically used for hypersonic vehicle nose caps and leading edges, rocket nozzle inserts, plasma-facing components and re-entry thermal protection. In short: 1600 °C UHTC composite; electrically conductive, EDM-machinable; stiffest composite in family.
What is the tensile strength of ZrB2-SiC?
ZrB2-SiC has a typical tensile strength of 320 MPa (46.4 ksi) — stronger than 57% of composite grades. Strength varies by condition: see the 7 listed tempers.
Is ZrB2-SiC easy to machine?
Not especially — machinability is rated not recommended (8/100, worse than 94% of composite grades). Diamond grinding/lapping only for conventional cutting; because ZrB2-SiC is electrically conductive it can be wire- and sinker-EDM machined, which is the practical route for complex leading-edge geometries.
Can ZrB2-SiC be welded?
Not weldable; joining is by active brazing (Ti/Zr-bearing filler), reaction bonding, or mechanical/co-sintered attachment to metallic or C/C substructures.
What surface finishes work on ZrB2-SiC?
Diamond lapping/polishing to sub-µm Ra; oxidation-protective or emissivity coatings (SiC CVD, silicide, HfO2-based) are often applied for repeated re-entry cycles.
Can ZrB2-SiC be formed, bent or molded?
Shaped by hot pressing, spark plasma sintering, or pressureless sintering (with B4C/C/MoSi2 aids) from green bodies made by cold pressing, slip/tape casting or additive-manufactured preforms; near-net shaping is preferred because post-sinter machining is very costly.
What is the maximum service temperature of ZrB2-SiC?
ZrB2-SiC is rated for continuous use to about 1,600°C (2,912 °F), and briefly to 2,200°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does ZrB2-SiC cost?
ZrB2-SiC is a high-cost composite ($$$$), 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
- Ultra-High Temperature Ceramics: Materials for Extreme Environment Applications — Wiley/ACerS (2014)
- Journal of the American Ceramic Society — ZrB2-SiC property compilations (Fahrenholtz, Hilmas et al.) — ACerS (2012)
- ASM Engineered Materials Handbook Vol.4 — Ceramics and Glasses — ASM International (1991)
- Specialty UHTC hot-pressed ZrB2-SiC billet data (research/industrial suppliers) — various (2023)
- ZrB2 ZrB2-SiC / (2025)
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.