Pa66 polyamide 66 or nylon 66 typical application range:
Compared with Pa6, Pa66 is more widely used in the automotive industry, instrument housings and other products that require impact resistance and high strength requirements.
Injection molding process conditions:
Drying treatment: If the material is sealed before processing, then there is no need to dry. However, if the storage container is opened, it is recommended to dry it in hot air at 85C. If the humidity is greater than 0.2%, it is also necessary to carry out vacuum drying at 105 C for 12 hours.
Melting temperature: 260~290C. The product for glass additives is 275~280C. The melting temperature should be avoided above 300C.
Mold temperature: 80C is recommended. The mold temperature will affect the crystallinity, which will affect the physical properties of the product. For thin-walled plastic parts, if a mold temperature lower than 40C is used, the crystallinity of the plastic part will change with time, and in order to maintain the geometric stability of the plastic part, annealing treatment is required.
Injection pressure: usually between 750 and 1250 bar, depending on material and product design.
Injection speed: high speed (slightly lower for reinforced materials).
Runners and gates:
Since the setting time of the Pa66 is very short, the position of the gate is very important. The gate aperture should not be less than 0.5*t
(where t is the thickness of the plastic part). If a hot runner is used, the gate size should be smaller than with a conventional runner because the hot runner can help prevent premature solidification of the material. If you use a submerged gate, the minimum diameter of the gate
It should be 0.75mm.
Chemical and physical properties:
Pa66 has a higher melting point in polyamide materials. It is a semi-crystalline-crystalline material. Pa66 also maintains high strength and stiffness at higher temperatures. Pa66 is still hygroscopic after molding, the extent of which depends primarily on the composition of the material, the wall thickness and the environmental conditions. When designing a product, it is important to consider the effect of hygroscopicity on geometric stability. In order to improve the mechanical properties of Pa66, various modifiers are often added. Glass is the most common additive, and sometimes synthetic rubbers such as EPDM and SBR are added for improved impact resistance. Pa66 is less sticky and therefore very mobile (but not as good as Pa6). This property can be used to machine very thin components. Its viscosity is sensitive to temperature changes. The shrinkage of Pa66 is between 1% and 2%, and the addition of glass fiber additives can reduce the shrinkage to 0.2% to 1%. The shrinkage ratio is large in the flow direction and in the direction perpendicular to the flow direction. Pa66 is resistant to many solvents, but is less resistant to acids and other chlorinating agents.
Professional and top quality Power Tools essential condition
1.Power tools` motor realistic rated input power is 3 times than laser power.
1.Motor material determine the motor overload performance. It is silicon steel.Good silicon steel has high wearing coefficient and perfect radiation effect.
2.Commutator is silver alloy. Good commutator has high wearing coefficient.Because there is carbon brush contact and friction. Perfect wearing coefficient could enhance the motor using longevity.
3.Universal motor use rounded wire to contact commutator and silicon steel. There is copper and aluminum. Aluminum rounded wire is not overload and easily broken of overload loading. The copper rounded wire could bear or support big overloading.
4.Good fan could increase the radiation effect.
5.Total motor all 1.2.3.4.5 could establish a perfect long longevity motor.
6.Motor axle gear hard is about 45HRC.
7.Big gear hare is more than 48HRC or 48-52HRC.
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