Ceramic ring

tubularboron nitrideinsulation

Product overview
Boron nitride (hexagonal h‑BN) ceramic components for Hall Effect Thruster (HET) plasma/discharge chambers. Designed to withstand high temperatures and plasma bombardment while maintaining electrical insulation and favorable secondary electron emission characteristics to support stable thruster operation.

Applications and advantages
The plasma chamber is the core region for propellant ionization and is exposed to intense thermal loads and ion impact. h‑BN grades reduce erosion and contamination, improve ionization efficiency and thermal stability, and help maintain chamber geometry under repeated operation cycles. Available grades target different trade-offs between thermal conductivity, mechanical strength and electrical resistivity to match thruster designs.

Properties

• High thermal stability and resistance to plasma bombardment
• Electrical insulation with low secondary electron emission where specified
• Chemical inertness in common propellant environments (xenon, krypton)
• Surface smoothness and machinability for precision chamber geometries

Manufacturing and quality
Materials are produced from high‑purity raw powders and advanced sintering processes to ensure uniform microstructure and repeatable performance. Each batch is subject to thermal, electrical and plasma compatibility testing to meet aerospace requirements. Custom shapes and dimensions are available; technical support for integration and thruster performance optimization is provided.

Boron nitride material properties (selected grades)

• UHB: Main composition BN>99.7%; Color: White; Density: 1.6 g/cm³; Three‑point bending: 18 MPa; Compressive: 45 MPa; Thermal conductivity: 35 W/(m·K); Thermal expansion (20–1000°C): 1.5×10^-6/K; Max use temp (Atm / Inactive gas / High vacuum long time): 900 / 2100 / 1800 °C; Room resistivity: >10^14 Ω·cm; Typical application: nitrides sintering.
• HB: Main composition BN>99%; Color: White; Density: 2.0 g/cm³; Three‑point bending: 35 MPa; Compressive: 85 MPa; Thermal conductivity: 40 W/(m·K); TEC: 1.8×10^-6/K; Max temp: 900 / 2100 / 1800 °C; Resistivity: >10^14 Ω·cm; Application: high‑temperature furnaces.
• BC: Main composition BN>97.5%; Color: White; Density: 2.0–2.1 g/cm³; Three‑point bending: 35 MPa; Compressive: 70 MPa; Thermal conductivity: 32 W/(m·K); TEC: 1.6×10^-6/K; Max temp: 900 / 2100 / 1900 °C; Resistivity: >10^13 Ω·cm; Application: high‑temperature furnaces.
• BMS: BN+SiO2; Color: White/Graphite; Density: 2.2–2.3 g/cm³; Three‑point bending: 65 MPa; Compressive: 145 MPa; Thermal conductivity: 35 W/(m·K); TEC: 2.0×10^-6/K; Max temp: 900 / 1750 / 1750 °C; Resistivity: >10^3 Ω·cm; Application: powder metallurgy.
• BMA: BN+A2O3; Color: White/Graphite; Density: 2.25–2.35 g/cm³; Three‑point bending: 65 MPa; Compressive: 145 MPa; Thermal conductivity: 35 W/(m·K); TEC: 2.0×10^-6/K; Max temp: 900 / 1750 / 1750 °C; Resistivity: >10^3 Ω·cm; Application: high‑temperature furnaces.
• BSC: BN+SiC; Color: Greyish‑Green; Density: 2.4–2.5 g/cm³; Three‑point bending: 80 MPa; Compressive: 175 MPa; Thermal conductivity: 45 W/(m·K); TEC: 2.8×10^-6/K; Max temp: 900 / 1800 / 1800 °C; Resistivity: >10^2 Ω·cm; Application: powder metallurgy.
• BMZ: BN+ZrO2; Color: White/Graphite; Density: 2.8–2.9 g/cm³; Three‑point bending: 90 MPa; Compressive: 220 MPa; Thermal conductivity: 30 W/(m·K); TEC: 3.5×10^-6/K; Max temp: 900 / 1800 / 1800 °C; Resistivity: >10^12 Ω·cm; Application: metal casting.
• BAN: BN+AlN; Color: Greyish‑Green; Density: 2.8–2.9 g/cm³; Three‑point bending: 90 MPa; Compressive: 220 MPa; Thermal conductivity: 85 W/(m·K); TEC: 2.8×10^-6/K; Max temp: 900 / 1750 / 1750 °C; Resistivity: >10^3 Ω·cm; Application: powder metallurgy.
• BSN: BN+Si3N4; Color: Gray/Black; Density: 2.2–2.3 g/cm³; Three‑point bending: / ; Compressive: 400–500 MPa; Thermal conductivity: 20–22 W/(m·K); TEC: / ; Max temp: 900 / 1750 / 1700 °C; Resistivity: / ; Application: metal casting.

Technical specifications

• Material: Hexagonal boron nitride (h‑BN), available in multiple grades (UHB, HB, BC, BMS, BMA, BSC, BMZ, BAN, BSN).
• Purity: up to BN > 99.7% (UHB); other grades contain BN with controlled additives.
• Density: ~1.6 to ~2.9 g/cm³ depending on grade.
• Mechanical strength: three‑point bending ~18–90 MPa; compressive strength ~45–500 MPa depending on grade.
• Thermal conductivity: ~20–85 W/(m·K) by grade; thermal expansion: ~1.5–3.5×10^-6/K (20–1000°C) for many grades.
• Maximum continuous use temperature: typically up to 900°C in atmosphere and significantly higher (up to ~2100°C in inert gas or high vacuum) depending on grade.
• Electrical insulation: very high resistivity for high‑purity grades (>10^12–10^14 Ω·cm).
• Manufacturing: high‑purity powders, advanced sintering, batch testing for thermal, electrical and plasma compatibility; custom geometries and technical integration support available.