What are the materials of the injection molding screw?
What are the materials of the injection molding screw?
The material of screw material of injection molding machine has 45 steel, 40Cr, ammonifying steel and 38CrMOAl. 1) no.45 steel is cheap, processing function is good, but wear-resistant and anti-corrupting function is poor. Thermal treatment: hb220-270, high frequency quenching HRC45-48 2) 40Cr can be better than 45 steel, but it tends to be coated with chromium to improve its ability to endure decay and wear resistance. However, the chromium plating layer is high, the coating is too thin and easy to wear, too thick and easy to flake off, and after stripping, it can accelerate the rot, so far less application. 3) the comprehensive functional ratio of nitride steel and 38CrMoAl is better than that of the force. The general nitrogen layer reaches 0. 4-0. 6 mm. But this material is low in resistance to hydrogen chloride and is costly. Thermal treatment of hb220-270, nitrous HRC >65, a method to improve the decay resistance of the screw profile, but it is reported that its wear resistance is not good enough. A series of steps have been taken in foreign countries in improving the wear resistance and decay of the screw. One method is to adopt high - wear-resistant and corrupt alloy steel. Such as 34CrAlNi, 31CrMo12, etc. It also adopts alloy material with high abrasion resistance and corrosion resistance.
The importance of material selection is the tension component of the injection molding machine. It is used to transport, compaction, melt, stir and press the plastic. All of these are accomplished through the rotation of the screw in the cylinder. In the rotation of the screw, the plastic can be used against the inner wall of the cylinder, the bottom of the screw, the advancing surface of the screw, and the friction and interaction between the plastic and the plastic in the city. The moving forward of plastic is the result of this combination of activities, and the heat from friction is also absorbed to improve plastic temperature and melt plastic. The placement of the screw will directly affect the level of these effects. Therefore, the black and white of the screw material directly affects the function of the injection molding machine, and also directly affects the life of the screw. At present, the screw in the sea is mostly imported, and may be compound material. Once the sink of its profile is cracked, the entire screw will be scrapped. The domestic screw can be used when extruding ordinary materials. The demand of the mining industry cannot be met once the product of strength and corruption is extruding. Corruption is quick.
