Wear-resistant nylon materials mainly by adding carbon fiber, molybdenum disulfide, graphite, polytetrafluoroethylene powder or silicone powder and other wear-resistant additives to nylon to reduce the friction coefficient or wear amount of nylon, the amount of these additives is generally between 3% and 15%. In general, wear-resistant nylon is mainly used in the field of mechanical parts, for the manufacture of various wear-resistant products (injection molding), such as bearing retainers, bushings, anti-friction rings, anti-friction pads, etc. In recent years, wear-resistant nylon has been widely used in the automotive field.

Compared with pure nylon resin, wear-resistant nylon has lower friction coefficient, better wear resistance and self-lubrication, while having higher mechanical properties and good heat resistance, oil resistance and chemical resistance, it also greatly reduces the water absorption and shrinkage of raw materials.

There are many improved varieties of self-lubricating wear-resistant nylon, such as graphite nylon PA12, graphite nylon PA66, graphite nylon PA12, carbon fiber nylon, nylon/molybdenum disulfide, nylon/polytetrafluoroethylene and nylon 1010/ molybdenum disulfide. Graphite nylon is especially suitable for wear-resistant lubricating materials, this is because graphite is often used as a lubricant in the machinery industry, lubricating oil can not be used at high speed, high temperature and high pressure, and graphite wear-resistant materials can slide at a high speed of 200~2000 ° C, working in the absence of lubricating oil, graphite materials are widely used in many corrosive media conveying equipment, Such as piston cups, seals and bearings, the operation does not need to add lubricating oil, graphite emulsion is also a good lubricant for many metal processing.

However, some mechanical parts (such as gaskets for transmission gears) have high requirements for accuracy in the thickness direction, so strict requirements are put forward for the uniformity of nylon materials in the thickness direction. Traditional wear-resistant nylon products are easy to produce concave effect on the end face due to thermal shrinkage and other factors. In particular, the size difference between core shrinkage and edge shrinkage of thick parts is a prominent problem, which can only be used after targeted improvement. This is also the difficulty of technical implementation, that is, how to improve the dimensional accuracy of the product on the basis of ensuring the wear-resistant effect, and the cost is not too high.

Several commonly used wear-resistant additives

(1) Carbon fiber

Carbon fiber can greatly improve the integrity of the material structure, load resistance and wear resistance. Unlike glass fiber, carbon fiber is a softer and less scratchy fiber, and carbon fiber will not scratch the friction surface of iron or steel against which it is rubbed.

(2) Molybdenum disulfide

Molybdenum disulfide is a wear-resistant additive mainly used in nylon plastics. Molybdenum disulfide acts as a crystallizing agent to increase the crystallinity of nylon so that the nylon material produces a harder and more wear-resistant surface. Molybdenum disulfide has a high affinity for metals, and once adsorbed on the metal surface, molybdenum disulfide molecules will fill the pores on the metal surface that can be seen with a microscope and make the metal surface smoother, which makes molybdenum disulfide an ideal wear-resistant additive for nylon and metal friction occasions.

(3) Graphite

The chemical structure of graphite is a unique lattice structure, this unique chemical structure makes graphite molecules easily slide each other when subjected to little friction, this wear resistance is especially important in the environment with water, so graphite as an ideal wear-resistant additive used in many parts placed in water, such as water shell, wheel blade and so on.

(4) Polytetrafluoroethylene (PTFE)

PTFE has a very low coefficient of friction, and PTFE molecules form a lubricating film on the surface of the part during friction. PTFE has good lubricity and wear resistance under friction, and is the best wear resistant additive in high load applications. These high-load applications include hydraulic piston ring seals and thrust washers. The PTFE content in amorphous plastics is generally 15%, and in crystalline plastics is generally 20%.

(5) Silicone

Silicone, the scientific name is generally called polysiloxane (or polydimethylsiloxane), low molecular weight polysiloxane liquid commonly known as silicone oil, ultra-high molecular weight polysiloxane appearance is white particles or powder, mainly used as plastic processing AIDS, to overcome the traditional silicone oil processing trouble and performance deficiencies, it can significantly reduce the friction coefficient of plastics, improve smoothness, improve surface luster, Improve scratch resistance, while having good stability and non-migration.