The present invention provides a paper ball-like graphene microsphere, a composite material thereof, and a preparation method therefor. Such paper ball-like graphene microspheres are obtained by chemically reducing graphene oxide microspheres to slowly remove oxygen-containing functional groups on the surface of the graphene oxide to avoid the volume expansion caused by rapid removal of the groups, thereby maintaining a tight bond between graphene sheets without separation; and removing the remaining small number of oxygen-containing functional groups and repairing defect structures in the graphene oxide sheets by means of high temperature treatment, such that the graphene structure becomes perfect at an ultrahigh temperature (2500 to 3000° C.), thereby further improving the bonding ability between the graphene sheets in the microspheres and achieving a dense structure.

A lubricant material for assisting machining process comprising a polyethylene oxide-polypropylene oxide copolymer having a weight average molecular weight of 5.0×10.sup.4 or more and 2.0×10.sup.5 or less.

A lubricant material for assisting machining process comprising a polyethylene oxide-polypropylene oxide copolymer having a weight average molecular weight of 5.0×10.sup.4 or more and 2.0×10.sup.5 or less.

The present disclosure relates to an anti-wear, anti-friction and stably-dispersed lubricating oil or grease, and the anti-wear, anti-friction and stably-dispersed lubricating oil or grease includes a main component of a lubricating oil or grease and a long carbon chain-grafted sulfonated graphene, the preparation method of which includes mixing a main component of a lubricating oil or grease with a long carbon chain-grafted sulfonated graphene, stirring and dispersing the mixture to obtain the product. The lubricating oil or grease in the present disclosure can significantly improve the long-term dispersion stability and dispersion stability in a complex environment by adding a long carbon chain-grafted sulfonated graphene in the main component, and at the same time can significantly improve the friction coefficient, which can significantly improve the anti-wear and anti-friction properties of the lubricating oil or grease, reduce the diameter of wear scars, and reduce the wear of copper and iron.

A bearing assembly is disclosed that includes a first component with a first bearing surface, and a second component with a second bearing surface. A fluid is disposed between the first bearing surface and the second bearing surface supporting the first bearing surface and the second bearing surface in a non-contact rotational relationship. The first bearing surface, or the second bearing surface, or both the first bearing surface and the second bearing surface include a surface layer with solid lubricant 2D nanoparticles in a matrix.

A bearing assembly is disclosed that includes a first component with a first bearing surface, and a second component with a second bearing surface. A fluid is disposed between the first bearing surface and the second bearing surface supporting the first bearing surface and the second bearing surface in a non-contact rotational relationship. The first bearing surface, or the second bearing surface, or both the first bearing surface and the second bearing surface include a surface layer with solid lubricant 2D nanoparticles in a matrix.

A method for inspecting a lubricant oil composition containing a base oil and a fullerene, the method including: measuring at least one of a lamellar length of the lubricating oil composition and a most abundant diameter in a particle size distribution obtained by a dynamic light scattering method, and selecting the lubricating oil composition whose measured value is within a set range.

The present invention relates to a lubricant composition comprising at least one graphite particle and at least one polytetrafluoroethylene particle.

It also relates to the use of said composition for the lubrication of gears, in particular of industrial gears.

The present invention relates to a lubricant composition comprising at least one graphite particle and at least one polytetrafluoroethylene particle.

It also relates to the use of said composition for the lubrication of gears, in particular of industrial gears.

A refrigerant compressor includes: a sealed container in which refrigerating machine oil is stored; an electric element accommodated in the sealed container and driven by electric power supplied from outside; and a compression element accommodated in the sealed container and covered with the refrigerating machine oil, the compression element being driven by the electric element to compress refrigerant gas supplied from outside. The refrigerating machine oil contains an oil film shortage adjusting agent in a dissolved state in such a concentration that deposition of the oil film shortage adjusting agent does not occur at least while the refrigerant compressor is operating.