Processing and forming conditions of PA46

The molding device should be cleaned at the start of the machine, and HDPE or

 otherclean compound can be used to clean up. Clean compounds must be able to 

withstand high temperatures to use.

In order to establish the optimum molding temperature, the upper and lower limits 

of the processing temperature of PA46 should be paid attention to. PA46 will 

produce decomposition when the melt is higher than 330 C, even if the residence

 time is very short. Low molding temperature can increase the retention time of the material.

The temperature setting of the cylinder, the design of the screw, the speed of the 

screw and the back pressure determine the temperature of the melt. Therefore, 

it is very important to measure the actual temperature of the melt after a period 

of injection molding and the stability of the molding conditions.

[barrel temperature] due to the high melting point and high crystallinity of PA46, 

when the PA46 degradation point is not too close to 330 degree C, the barrel

temperature needs to be set high enough to provide uniform melt.

[screw rotating speed], like most polyamides, PA46 has excellent fluidity due to

 its relatively low melt viscosity. The screw speed has a relatively low influence on 

the shear amount transferred to the PA46 melt, which usually uses a high screw 

speed without damaging the PA46 polymer. It is necessary to avoid reducing the

 length of glass fiber when the glass fiber is reinforced. Therefore, we should choose 

the screw speed as low as possible so that the plasticizing time of the screw is just

 in the cooling time of the molding cycle.

[back pressure] when processing PA46, it is recommended to use a back pressure

 equivalent to 7.5 bars to get a uniform melt and prevent the gas from being involved.

 High backpressure (such as 20 bars) will prolong the plasticizing time, produce casting

 and reduce the length of glass fiber.

[speed / pressure] because of the fast curing rate of PA46, it requires a higher speed

 to obtain excellent compacted melts and surface finish. Therefore, the exhaust of

 the mold is needed to avoid the burning of the end of the channel.

The compression pressure / holding time is the best appearance and size control for the

 plastic parts, and the pressure holding time plays an important role. In theory, the holding

 time is the time needed to solidify the gate.  Compared with other engineering plastics,

 PA46 usually requires only a very short holding time due to its rapid solidification 

characteristics. It can reduce the sag and hole caused by the volume contraction through

 the long enough pressure protection stage. However, the pressure protection should 

not be too high to avoid the stress. One way to determine the correct pressure level is

 to increase the pressure pressure until the depression is not seen.  After the complete 

cooling, it is cut at the thickest part of the plastic part to check if there is a hole. If necessary,

 the pressure protection pressure can be increased. One way to determine the holding time is 

to measure the weight of the plastic part, and then increase the holding time until the constant

 weight is obtained. A more complex approach is to install sensors in the cavity to determine 

the exact setting time of the gate. Compared with PA66, PA46 needs only about half of the 

holding time. This combined with its higher mold temperature can explain why PA46 has a 

shorter period of time than other engineering plastics.

[die temperature / cooling time] because the PA46 curing speed is very fast, so its cooling 

time is also very short.  For this reason, the plasticizing time is usually the determinant of the

 molding cycle. In theory, the processing process of PA46 can be carried out within a wide 

range of die temperatures. In order to obtain good dimensional stability and fluidity, the 

recommended die temperature should be higher than 80 C. In order to reduce the later

 shrinkage, increase fluidity, improve the strength of weld line and improve toughness and

 surface quality, the die temperature can be increased to 120 degree C or even higher.

[open model]PA46 usually does not adhere to the surface of the mold and has good 

demoulding characteristics.  Because of its high crystallinity, PA46 has fast curing and

 high rigidity at high temperature. So the injection parts of PA46 can be removed at 

a relatively high temperature, such as 200 C, so that the molding cycle can be shortened.

[production stoppage] when the production process is going to stop for a short time,

 the hopper should be closed, the cylinder will be emptied and the screw is in the front

 position, and the temperature of the barrel can be maintained. For 1 ~ 2 hours of 

production stop, the same step should be adopted, but the temperature of the barrel 

should be reduced to 260 C. When the machine is opened, the new material is used to

 flush the barrel. For flame-retardant grade, the barrel should be washed with HDPE before the machine is pause.

[shutdown / cleaning] the hopper should be emptied at the end of PA46 production,

 and a high viscosity grade of HDPE is used to flush the barrel. The temperature range of 

the barrel is reduced to the temperature range of the next polymer to be processed.

1. combustible materials


2. with easy processability and excellent flow performance


3. excellent tensile strength and good adiabatic performance


4. flame retardant; electroplating; heat-resistant; heat-resistant


5. high stiffness keep performance, and show good high temperature resistance to vermicular.


6. stiffness and creep modulus of PPS, PEI and PES due to the same glass enhancement degree


7. it can be used for parts with a thin-walled part to reach 0.1 millimeters without flfei.