Boron nitride is an excellent and highly potential new ceramic material, consisting of five isomers: Hexagonal Boron Nitride (H-BN), Cubic Boron Nitride (C-BN), Wurtzite Boron Nitride (W-BN), Rhombohedral Boron Nitride (R-BN), and Orthorhombic Boron Nitride (o-BN). Boron nitride powder is characterized by its loose texture, lubricity, light weight, and moisture absorption, and it is white in color.

What is the development of boron nitride ceramic materials?

Category: Industry News Author: Source: Date: May 13, 2022

Boron nitride is a high-performance, promising new ceramic material with five isomers: Hexagonal Boron Nitride (H-BN), Cubic Boron Nitride (C-BN), Wurtzite Boron Nitride (W-BN), Rhombohedral Boron Nitride (R-BN), and Orthorhombic Boron Nitride (o-BN). Boron nitride powder is characterized by its loose, lubricious, lightweight nature, and moisture absorption; it is white in color.

Physical and Chemical Properties of Boron Nitride Ceramics

Boron Nitride Thermal Properties: Boron nitride products can be used in an oxidizing atmosphere at approximately 1000℃ and in an inert atmosphere near 3000℃. This performance surpasses that of mullite, aluminum oxide, and silicon carbide. Additionally, it boasts high thermal resistance and impact resistance, ensuring it won't crack during rapid cooling and heating cycles at 1500℃.

(2) Boron nitride chemical stability: It does not react with the majority of metals, such as dissolved iron, aluminum, copper, silicon, potassium arsenide, brass, and cryolite, nor does it react with slag glass. Therefore, containers made from boron nitride materials can be used for these substances. However, those containing B2O3 generally have hygroscopic properties, which causes the product to absorb moisture and develop cracks when rapidly heated during use. One effective measure to improve this drawback is to add some binder.

(Boron Nitride Electrical Properties: Due to the low dielectric constant and dielectric loss of BN products, they can be widely used in both high-frequency and low-frequency ranges. Its dielectric strength is 4.5 times that of aluminum oxide, and its dielectric constant is half that of aluminum oxide. Its electrical properties differ significantly from those of graphite. Like oxide ceramics, it has no conductivity at high temperatures. It is an electrical insulating material that can be used over a wide temperature range.)

(4) Boron Nitride Machinability: The Mohs hardness of BN ceramics is 2, making it machinable on lathe, milling machines, and other processing equipment. It can also be processed into thin plates, spirals, and various complex-shaped parts. BN has lower mechanical strength. While it is superior to graphite at room temperature, it is more brittle than oxide ceramics.

(5) Boron Nitride Lubricity: BN powder is hexagonal crystal system. It is a white, sheet-like fine material, similar to graphite. It is commonly referred to as white graphite, known for its good lubricity.

Boron Nitride (BN) is one of the lighter ceramics materials.

(7) Boron nitride's neutron absorption properties: BN possesses a large neutron absorption cross-section.