Truck door handle parts

Material:PA66

What is injection molding?
Injection moulding is a manufacturing process for producing parts by injecting molten material into a mould, or mold. Injection moulding can be performed with a host of materials mainly including metals (for which the process is called die-casting), glasses, elastomers, confections, and most commonly thermoplastic and thermosetting polymers. Material for the part is fed into a heated barrel, mixed (using a helical screw), and injected into a mould cavity, where it cools and hardens to the configuration of the cavity. Injection moulding is widely used for manufacturing a variety of parts, from the smallest components to entire body panels of cars. Advances in 3D printing technology, using photopolymers that do not melt during the injection moulding of some lower-temperature thermoplastics, can be used for some simple injection moulds.

What are the application scope and production parameters of nylon 66 injection molded parts?

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 mold process conditions:
Drying treatment: If the material is sealed before processing, then there is no need to dry it. However, if the storage container is opened, it is recommended to dry it in hot air at 85°C. If the humidity is greater than 0.2%, vacuum drying at 105°C for 12 hours is required.
Melting temperature: 260~290℃. For glass additive products, the temperature is 275~280℃. The melting temperature should not be higher than 300°C.
Mold temperature: 80°C is recommended. The mold temperature will affect the crystallinity, and the crystallinity will affect the physical properties of the product. For thin-walled plastic parts, if a mold temperature lower than 40°C is used, the crystallinity of the plastic parts will change with time. In order to maintain the geometric stability of the plastic parts, annealing treatment is required.
Injection pressure: usually 750~1250bar, depending on the material and product design.
Injection speed: high speed (slightly lower for reinforced materials).
Runner and gate: Since the solidification time of PA66 is very short, the location 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 you use a hot runner, the gate size should be smaller than using a conventional runner, because the hot runner can help prevent premature solidification of the material. If a submerged gate is used, the minimum diameter of the gate should be 0.75mm.

What are the chemical and physical properties of nylon 66?

PA66 has a higher melting point in polyamide materials. It is a semi-crystalline-crystalline material. PA66 can maintain strong strength and rigidity even at higher temperatures. PA66 is still hygroscopic after molding, its degree mainly depends on the composition of the material, wall thickness and environmental conditions. In product design, the influence of moisture absorption on geometric stability must be considered. 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 to improve impact resistance. PA66 has low viscosity, so it has good fluidity (but not as good as PA6). This property can be used to process very thin components. Its viscosity is very sensitive to temperature changes. The shrinkage rate of PA66 is between 1%~2%, adding glass fiber additives can reduce the shrinkage rate to 0.2%~1%. The shrinkage rate differs greatly in the direction of the flow and the direction perpendicular to the direction of the flow. PA66 is resistant to many solvents, but has weak resistance to acids and other chlorinating agents.