What are the properties and application characteristics of friction-reducing self-lubricating metal-ceramic composite powders

       The friction-reducing self-lubricating metal-ceramic composite powder material is made of soft material particles with low friction coefficient, low hardness and self-lubricating properties, such as graphite, MoS2, WS2, WSe2, NbSe2, CaF2, etc., as the composite powder of the core material . The coating material is a metal that can be well combined with the matrix and the coated particles have good lubricating ability, such as cobalt, nickel, copper, silver, iron, chromium, molybdenum, tungsten and tantalum. Coatings made of this type of composite powder are mostly used in kinematic friction of machinery that requires oil-free lubrication, dry friction, boundary lubrication and maintenance.



    1) Nickel (copper) clad molybdenum disulfide (Ni/MoS2) composite powder

    Under normal conditions, copper-clad molybdenum disulfide has better anti-friction and self-lubricating properties; but under high temperature conditions, nickel-clad molybdenum disulfide coatings are often used. These materials are suitable for high temperature, low temperature, high load (enough to destroy the lubricating oil film), high speed (prone to produce boundary lubrication or oil-free lubrication), chemical corrosion and anti-friction self-lubricating coatings under ultra-vacuum conditions. Such as self-lubricating coatings for liquid nitrogen equipment, self-lubricating coatings for space ultra-vacuum equipment, etc.

    Powder flame spraying (accelerated with compressed air) and plasma spraying can be used to prepare anti-friction self-lubricating coatings on metal substrates.

    2) High temperature self-lubricating composite powder

    This is a high-temperature self-lubricating coating material composed of cobalt oxide (CoO) and calcium fluoride (CaF2). Cobalt oxide is used as a binder, and calcium fluoride is a high-temperature self-lubricating component. The ratio of cobalt oxide and calcium fluoride is 1:3, and its friction coefficient decreases with the increase of operating temperature. This material is mainly made of high-temperature self-lubricating coating on the base of Inconel, and the coating is used as high-temperature bearing, etc. The high temperature self-lubricating coating used for high temperature forging and extrusion process can also be used as high temperature lubricant.

    3) Self-lubricating composite powder for high temperature and low temperature

    This is a multi-component metal-ceramic composite powder composed of silver powder, NiCr alloy powder and CaF2 powder. Such materials can be used in low temperature (-196°C) and high temperature (800°C~840°C) working conditions, such as rockets and space shuttles, liquid metal pumps and gas turbines subjected to rapid cooling and rapid thermal fatigue and vacuum conditions. Preparation of self-lubricating coatings on bearings, etc.

    Self-lubricating coatings can be prepared on heat-resistant alloy substrates by gas-stable plasma spraying.