FabDigit

BeO

Toxic-to-process but exceptionally high thermal-conductivity oxide ceramic combining electrical insulation with metal-like heat spreading; used where standard alumina cannot dissipate heat fast enough.

High cost $$$$

Reference datasheet — BeO 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 995 condition

BeO tempers and conditions

BeO is supplied in 3 conditions, soft to hard. 995 is the default FabDigit quotes; the values on this page are for it.

Compare all 3 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
995Default
BeO 99.5 %
Industry workhorse at 99.5 % purity: choose when thermal conductivity, strength and metallizability must be balanced for microwave tubes, laser heat sinks and thick-film power substrates.1301,200 HV275 W/m·K
BeO 99.0 %
Pick the lower-cost pressureless-sintered 99.0 % purity quality for power-resistor substrates and insulating parts that need less than 250 W/m·K thermal conductivity.1,100 HV240 W/m·K
BeO 99.8 % hot-pressed / near-theoretical-density grade
Choose the hot-pressed, near-theoretical-density 99.8 % quality for extreme power-density heat sinks, nuclear moderator parts and high-frequency windows; near-zero porosity yields 310 W/m·K.1,280 HV310 W/m·K

What is BeO?

Toxic-to-process but exceptionally high thermal-conductivity oxide ceramic combining electrical insulation with metal-like heat spreading; used where standard alumina cannot dissipate heat fast enough. BeO has a density of 2.87 g/cm³ (0.104 lb/in³), lighter than 77% of ceramic grades. It melts at 2,530°C (4,586 °F). BeO has a tensile strength of 130 MPa (18.9 ksi), stronger than 53% of ceramic grades. The elastic modulus is 345 GPa (50 Msi).

What is BeO used for?

  • RF/microwave substrates
  • laser diode heat sinks
  • high-power electronic packages
  • nuclear moderator components

Advantages

  • Conducts heat well — 275 W/m·K (158.9 BTU/hr·ft·°F), better than 97% of ceramic grades
  • High service temperature — 1,800°C (3,272 °F), better than 92% of ceramic grades
  • Lightweight — 2.87 g/cm³ (0.104 lb/in³), better than 77% of ceramic grades

Limitations

  • High embodied carbon — 30 kg CO₂/kg, worse than 91% of ceramic grades

BeO properties

Typical room-temperature values for BeO-995; bars are the position among ceramic grades.

Physical4

BeO has a density of 2.87 g/cm³ (0.104 lb/in³), lighter than 77% of ceramic grades. It melts at 2,530°C (4,586 °F).

Density2.87 g/cm³0.1 lb/in³
Melting Point (Solidus)2,530°C4,586 °F
Refractive Index1.719
Porosity0.5%

Mechanical11

BeO has a tensile strength of 130 MPa (18.9 ksi), stronger than 53% of ceramic grades. The elastic modulus is 345 GPa (50 Msi).

Elastic (Young's) Modulus345 GPa50 Msi
Shear Modulus137 GPa19.9 Msi
Bulk Modulus240 GPa34.8 Msi
Poisson's Ratio0.26
Tensile Strength (Ultimate)130 MPa18.9 ksi
Compressive Strength1,550 MPa225 ksi
Flexural Strength200 MPa29 ksi
Fracture Toughness (K_IC)3.5 MPa·√m3.2 ksi·√in
Hardness, Vickers1,200 HV
Hardness, Knoop1,200 HK
Hardness, Mohs9

Thermal5

BeO is rated for continuous service to 1,800°C (3,272 °F). It conducts heat at 275 W/m·K (158.9 BTU/hr·ft·°F), better than 97% of ceramic grades. Thermal expansion is 7 µm/m·K (3.89 µin/in·°F).

Thermal Conductivity275 W/m·K159 BTU/hr·ft·°F
Specific Heat Capacity1,030 J/kg·K0.25 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)7 µm/m·K3.9 µin/in·°F
Max Service Temperature (continuous)1,800°C3,272 °F
Min Service Temperature-269°C-452 °F

Electrical5

BeO is an electrical insulator with a dielectric strength of 12 kV/mm (304.8 V/mil) and a resistivity of 1×10¹⁴ Ω·m.

Electrical Resistivity1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
Dielectric Strength12 kV/mm305 V/mil
Dielectric Constant (1 MHz)6.7
Dissipation Factor (1 MHz)3×10⁻⁴
Volume Resistivity1×10¹⁶ Ω·cm

Chemical & Environmental2

Corrosion resistance is very good (82/100), better than 61% of ceramic grades.

Corrosion ResistanceVery good82/100
Chemical Resistance Summary—

Sustainability4

Producing a kilogram of BeO takes about 450 MJ of energy and emits 30 kg of CO₂ — more than 94% of ceramic grades. Typical recycled content is 5%.

Embodied Energy (primary production)450 MJ/kg193,465 BTU/lb
Embodied Carbon (primary production)30 kg CO₂/kg
Embodied Water500 L/kg59.9 gal/lb
Typical Recycled Content5%

Manufacturability3

BeO's machinability is not recommended (5/100, worse than 59% of ceramic grades).

MachinabilityNot recommended5/100
PolishabilityVery good70/100
Sintering / Firing Temperature1,650°C3,002 °F

Common Calculations4

Specific Strength (UTS / density)calculated45 kN·m/kg
Specific Stiffness (E / density)calculated120.2 MN·m/kg
Thermal Diffusivitycalculated93 mm²/s
Thermal Shock Resistance Indexcalculated15

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. BeO is highlighted; hover a dot for its name, or open the interactive family chart.

501002005001,000234567Density (g/cm³)Yield strength (MPa) — log scale

Working with BeO

Is BeO easy to machine?

After sintering, only diamond grinding or laser machining is practical, and all work must be run wet with HEPA extraction; dry dust generation is prohibited. Turn or mill complex geometry in the green state and sinter afterwards.

Can BeO be welded?

Not weldable; hermetic joints are made by Mo-Mn metallising plus nickel plating, then brazing to Kovar or copper with Ag-Cu filler.

Can BeO be formed, bent or molded?

Formed by dry pressing, isostatic pressing or tape casting for thin substrates, then sintered at 1500–1800 °C. Linear shrinkage is about 15–20 %, so tooling must be oversized accordingly.

BeO 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.

ElementSpec limit (wt %)Nominal
BeOmain crystalline phase, hexagonal wurtzite structure99.5 – 99.999.5
MgOcommon sintering aid, inhibits grain growth0 – 0.30.15
SiO2impurity/sintering aid0 – 0.20.08
Al2O3impurity0 – 0.150.05
Fe2O3 + CaO + otherbalance of trace impurities, total <0.1 %balance

What surface finishes work on BeO?

Diamond lapping and polishing reach Ra below 0.1 µm. Surfaces accept thick-film or thin-film metallisation (Ti-Pt-Au, Mo-Mn, DBC copper) for soldering and circuit routing.

Equivalent designations

Standards and trade names that resolve to BeO in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

Also called
BeO 99.5%

How much does BeO cost?

BeO 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.

BeO — frequently asked

What is BeO used for?

BeO is typically used for RF/microwave substrates, laser diode heat sinks, high-power electronic packages and nuclear moderator components. In short: highest-conductivity oxide insulator; toxic dust, contained processing; alternative to aluminium nitride.

What is the tensile strength of BeO?

BeO has a typical tensile strength of 130 MPa (18.9 ksi) — stronger than 53% of ceramic grades. Strength varies by condition: see the 3 listed tempers.

Is BeO easy to machine?

Not especially — machinability is rated not recommended (5/100, worse than 59% of ceramic grades). After sintering, only diamond grinding or laser machining is practical, and all work must be run wet with HEPA extraction; dry dust generation is prohibited. Turn or mill complex geometry in the green state and sinter afterwards.

Can BeO be welded?

Not weldable; hermetic joints are made by Mo-Mn metallising plus nickel plating, then brazing to Kovar or copper with Ag-Cu filler.

What surface finishes work on BeO?

Diamond lapping and polishing reach Ra below 0.1 µm. Surfaces accept thick-film or thin-film metallisation (Ti-Pt-Au, Mo-Mn, DBC copper) for soldering and circuit routing.

Can BeO be formed, bent or molded?

Formed by dry pressing, isostatic pressing or tape casting for thin substrates, then sintered at 1500–1800 °C. Linear shrinkage is about 15–20 %, so tooling must be oversized accordingly.

What is the maximum service temperature of BeO?

BeO is rated for continuous use to about 1,800°C (3,272 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

How much does BeO cost?

BeO 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

  1. ASM Engineered Materials Handbook, Vol. 4: Ceramics and Glasses — ASM International (1991)
  2. Beryllium Oxide (BeO) Ceramic Property Data — American Beryllia / Materion Ceramics (2022)
  3. Engineering ceramics thermophysical property compilation — NIST / Ceramic Industry data tables (2020)

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.