Hexagonal boron nitride (h-BN) powder is an exceptional solid lubricant material. Due to its microscopic structure resembling graphite and its white color, it is hailed as “white graphene.” Its unique layered crystal structure endows it with outstanding lubricating properties, demonstrating irreplaceable application value under high temperatures and extreme conditions.
Exceptional Lubricating Properties
h-BN's lubricity stems from its layered structure. Each layer consists of alternating boron and nitrogen atoms forming hexagonal planar networks, with layers bonded by weak van der Waals forces. Under shear stress, interlayer slip occurs readily, significantly reducing the coefficient of friction. Unlike graphite, h-BN's lubricity does not depend on adsorbed gases like water vapor, maintaining stability even under high vacuum conditions. More notably, it retains outstanding lubrication performance in oxidizing atmospheres up to 900°C and inert atmospheres up to 1200°C. It also exhibits chemical stability, being insoluble in most molten metals and acids.
Wide Range of Applications
With these properties, h-BN powder has become a key material in multiple high-end industrial sectors:
High-Temperature Lubricants: Widely used in aerospace and metallurgical industries for high-temperature bearings, mold release agents, and welding coatings, addressing the challenge of carbonization failure in conventional lubricants.
High-Performance Composites: Incorporated as reinforcing fillers in ceramic, resin, and metal matrix composites, it enhances wear resistance and reduces friction while improving thermal conductivity and mechanical strength.
Cosmetics: Utilized as an additive in premium foundations and talcum powders for its smooth skin feel and excellent coverage, delivering a silky texture.
Electronics Industry: Demonstrates lubricity, high thermal conductivity, and insulation properties in thermally conductive insulating plastics and thermal pads.
In summary, hexagonal boron nitride powder, with its unique high-temperature stability, chemical inertness, and exceptional solid lubrication capabilities, has become an indispensable high-performance material spanning heavy industry to daily life, continuously driving technological advancement and industrial upgrading.
