BeO Ceramic BeO-99.5
Grade · default condition
Default choice for microwave windows, TWT rods and power-device heat spreaders where ~285 W/m·K and metallizable surfaces are required.
Values for the BeO-99.5 condition
Other BeO Ceramic tempers and conditions
BeO Ceramic is listed in 4 conditions; see the grade overview at BeO Ceramic.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
general technical grade | Cost-reduced sintered grade for insulator bushings, resistor cores and crucibles where ~250 W/m·K is sufficient. | — | 130 | — | 1,150 HV | 250 W/m·K |
economy grade with higher glassy phase | Lowest-cost beryllia body for bulk insulators and crucibles; extra sintering aids cut thermal conductivity noticeably. | — | — | — | 1,050 HV | 210 W/m·K |
BeO-99.5DefaultThis page pressureless sintered, standard electronic grade | Default choice for microwave windows, TWT rods and power-device heat spreaders where ~285 W/m·K and metallizable surfaces are required. | — | — | — | 1,200 HV | 285 W/m·K |
high-purity / hot-pressed, maximum thermal conductivity | Pick when peak thermal conductivity and lowest RF loss matter — high-power TWT/klystron windows and laser heat sinks. | — | — | — | 1,300 HV | 320 W/m·K |
What is BeO Ceramic BeO-99.5?
BeO Ceramic BeO-99.5 is BeO Ceramic in the BeO-99.5 grade — default choice for microwave windows, TWT rods and power-device heat spreaders where ~285 W/m·K and metallizable surfaces are required. BeO Ceramic BeO-99.5 has a tensile strength of 140 MPa (20.3 ksi), stronger than 54% of ceramic grades. The elastic modulus is 345 GPa (50 Msi). BeO Ceramic BeO-99.5 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).
Advantages
- Conducts heat well — 285 W/m·K (164.7 BTU/hr·ft·°F), better than 98% 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
BeO Ceramic BeO-99.5 properties
Typical room-temperature values for BeO Ceramic BeO-99.5; 10 are specific to this condition. Other listed values are BeO Ceramic reference data and may not represent this condition. Bars are the position among ceramic grades.
Physical4
BeO Ceramic BeO-99.5 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).
Mechanical11
BeO Ceramic BeO-99.5 has a tensile strength of 140 MPa (20.3 ksi), stronger than 54% of ceramic grades. The elastic modulus is 345 GPa (50 Msi).
Thermal5
BeO Ceramic BeO-99.5 is rated for continuous service to 1,800°C (3,272 °F). It conducts heat at 285 W/m·K (164.7 BTU/hr·ft·°F), better than 98% of ceramic grades. Thermal expansion is 7 µm/m·K (3.89 µin/in·°F).
Electrical5
BeO Ceramic BeO-99.5 is an electrical insulator with a dielectric strength of 12 kV/mm (304.8 V/mil) and a resistivity of 1×10¹³ Ω·m.
Chemical & Environmental2
Corrosion resistance is excellent (85/100), better than 69% of ceramic grades.
Sustainability4
Producing a kilogram of BeO Ceramic BeO-99.5 takes about 300 MJ of energy and emits 22 kg of CO₂ — more than 74% of ceramic grades. Typical recycled content is 5%.
Manufacturability3
BeO Ceramic BeO-99.5'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 BeO Ceramic BeO-99.5
Is BeO Ceramic easy to machine?
Green-state machining is strongly preferred; fired BeO needs wet diamond grinding/lapping with fully enclosed dust and slurry capture — dry machining is prohibited due to beryllium toxicity.
Can BeO Ceramic be welded?
Not weldable; joined by active-brazing or by Mo-Mn/Ni metallization plus Ag-Cu or Au-Sn brazing to Kovar, Cu or Mo.
Can BeO Ceramic be formed, bent or molded?
Formed by dry pressing, isostatic pressing, tape casting or slip casting of MgO-doped powder, then sintered at ~1500–1800 °C (hot pressing for maximum density).
What surface finishes work on BeO Ceramic?
Standard as-fired, lapped or polished surfaces; thick-film or thin-film (Ti/Pt/Au) metallization and electroless Ni/Au plating are routine for power-electronics substrates.
BeO Ceramic 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 |
|---|---|---|
| BeOberyllium oxide, main phase | 99 – 99.9 | 99.5 |
| MgOtypical sintering aid / grain-growth control | 0 – 0.5 | 0.25 |
| SiO2impurity / glassy phase | 0 – 0.2 | 0.1 |
| Al2O3impurity | 0 – 0.2 | 0.08 |
| other oxides (CaO, Fe2O3)trace | balance | — |
BeO Ceramic BeO-99.5 — frequently asked
What is BeO Ceramic BeO-99.5 used for?
BeO Ceramic BeO-99.5 is typically used for RF/microwave device substrates, laser heat sinks, high-power electronic packages and neutron moderator components. In short: highest thermal conductivity oxide; insulating heat spreader; requires beryllium dust control.
What is the tensile strength of BeO Ceramic BeO-99.5?
BeO Ceramic BeO-99.5 has a typical tensile strength of 140 MPa (20.3 ksi) — stronger than 54% of ceramic grades. Strength varies by condition: see the 4 listed tempers.
Is BeO Ceramic BeO-99.5 easy to machine?
Not especially — machinability is rated not recommended (5/100, worse than 59% of ceramic grades). Green-state machining is strongly preferred; fired BeO needs wet diamond grinding/lapping with fully enclosed dust and slurry capture — dry machining is prohibited due to beryllium toxicity.
Can BeO Ceramic BeO-99.5 be welded?
Not weldable; joined by active-brazing or by Mo-Mn/Ni metallization plus Ag-Cu or Au-Sn brazing to Kovar, Cu or Mo.
What surface finishes work on BeO Ceramic BeO-99.5?
Standard as-fired, lapped or polished surfaces; thick-film or thin-film (Ti/Pt/Au) metallization and electroless Ni/Au plating are routine for power-electronics substrates.
Can BeO Ceramic BeO-99.5 be formed, bent or molded?
Formed by dry pressing, isostatic pressing, tape casting or slip casting of MgO-doped powder, then sintered at ~1500–1800 °C (hot pressing for maximum density).
What is the maximum service temperature of BeO Ceramic BeO-99.5?
BeO Ceramic BeO-99.5 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.
Sources
- ASM Engineered Materials Handbook Vol. 4: Ceramics and Glasses — ASM International (1991)
- Beryllium Oxide Ceramic Property Data — Materion / American Beryllia (2022)
- GB/T 5593 (relevant electronic ceramic test methods) — SAC (2020)
- Engineering ceramics property tables (BeO) — MatWeb / CeramTec technical data (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.