ABS plastics and LDPE materials usually can not meet the requirements of lubrication, fatigue resistance, dimensional stability, heat resistance, creep resistance and chemical corrosion resistance of plastic gears. But it is also used in the field of low-grade sports transmission gears such as toys.
Thermoplastic elastomer moulded gear has good flexibility, which can absorb the impact load produced by transmission well, and make the gear noise low and run more smoothly. Commonly used copolyester thermoplastic elastomer moulds low power and high speed transmission gears, which can also reduce running noise even if some deformations and deviations occur during operation.
PC (polycarbonate) has the advantages of excellent impact resistance, weatherability, high hardness, small shrinkage and size stability. However, the self-wetting, chemical and fatigue properties of polycarbonate are poor. This material is colorless and transparent, easy to colour and beautiful plastic parts. It is still widely used in precision gear transmission of instruments and instruments and process decorations.
POM (polyformaldehyde) is one of the most commonly used and important thermoplastic engineering plastics for gears, which has a history of more than 40 years. Due to the special moisture absorption of polyformaldehyde, it can ensure the dimensional stability of gears for a long time and the excellent properties such as fatigue resistance and corrosion resistance in a wide temperature range. It has always been the preferred engineering plastics in plastic gears.
PPA (poly (p-phenylenediamine) has high thermal deformation stability, and can maintain its superior mechanical strength, hardness, fatigue resistance and creep resistance in a higher, wider temperature range and high humidity environment. In some PA6, PA66 gears can not withstand high temperature, high humidity and other conditions, still have the ability to work normally.
PA (nylon) has good toughness and durability, and is another common engineering plastic for gear. However, nylon has a strong hygroscopicity, which will cause changes in the performance and size of plastic parts. Therefore, nylon is not suitable for precision transmission gears.
LCP (liquid crystal polymer) has been successfully applied to micro plastic gears with small injection mold. This kind of gear has the characteristics of good dimensional stability, high chemical resistance and low forming shrinkage. This material is often used to mold miniature plastic gears for watches.
PPS (polyphenylene sulfide) has high hardness, dimensional stability, fatigue resistance, chemical resistance and characteristics, as well as long-term use temperature of up to 200 years meteorite dilution > stirring oyster faithful teeth cunning gutter, persistent and sincere amount of phlegm scratching.
PEEK (polyether ether ketone) and modified polymer have been successfully applied to high performance plastics in power transmission gears with large loads. This kind of material has the characteristics of high temperature resistance, high comprehensive mechanical properties, abrasion resistance and strong chemical corrosion resistance, and is the top plastics in moulding gear nowadays.
PBT (polyester) can mold a very smooth surface of the gear. The highest working temperature of the unfilled modified plastic parts can reach 150 centimeters. The working temperature of the non-filled plastic parts can reach as high as 170 centimeters. The value of the working temperature of the non-filled plastic parts can be as high as that of the old ones.