The technical characteristics of static liquid extrusion for titanium screws

Static liquid extrusion technology has a history of nearly a hundred years. However, during the process of large-scale and industrialization, due to the limitations of higher strength structural materials, the development speed has slowed down. With the advancement of materials science, this technology has been promoted for practical application. The static liquid extrusion technology for extruding titanium screws has outstanding advantages. In recent years, superconducting materials have been developing towards larger cross-sections. Due to the increasing requirements for continuous steepness, the size and weight of the billet need to be increased. Thus, using ordinary extrusion equipment is difficult to achieve, while using static liquid extrusion technology has many advantages.

During the metal processing process, it is desired that the processed parts be in a triaxial compressive stress state, as this is conducive to the plastic deformation of the metal and eliminates surface cracks and defects of the product. In addition, it is required to be in a good lubrication state during processing to reduce functional loss. If static liquid extrusion technology is adopted, these two purposes can be achieved.

1. Static liquid extrusion of titanium screws is in an unfrictional deformation process. The friction between the billet and the extrusion cylinder is the main obstacle to metal deformation. When using static liquid extrusion, high-pressure liquid separates the billet from the wall of the extrusion cylinder, and some high-pressure liquid enters the die hole and is separated from the extruded product. Therefore, the friction coefficient can be as low as below 0.01, thereby significantly reducing power loss and improving the surface accuracy of the product.

2. Increase the length of the billet for titanium screws. In the traditional extrusion method, 50% of the extrusion force is used to overcome the friction force between the billet and the cylinder wall. The size of the friction force is proportional to the toughness of the billet. Therefore, the length of the billet is limited. If static liquid extrusion is used, it is in an unfrictional extrusion process, so the length of the billet can be increased. For example, with the same tonnage of extrusion machine, the output of static liquid extrusion can be more than three times that of ordinary extrusion.