Screw the material requirements
By the extrusion process, screw at high temperature, corrosion, wear strong, working under high torque, so screw you must:
1) high temperature resistance, high temperature deformation;
2) abrasion resistant, long service life;
3) corrosion-resistant, the material is corrosive;
4) high strength, can withstand high torque, high speed;
5) has good machinability;
6) after heat treatment, residual stress and thermal deformation is small, and so on.