Multi-directional die forging is essentially a combined forming process in which extrusion and forging are combined with extrusion. Compared with ordinary die forging, the main features are:
(1) Multi-directional die forging can forge hollow forgings with more complex shapes, no burrs, no or small die forging, so that the forgings are as close as possible to the shape and size of the parts, thereby improving material utilization and reducing Cutting work hours, reducing product costs;
(2) Generally, multi-directional die forging requires only one heating and one-time stroke of the equipment to form forgings, thereby reducing the forging process, improving production efficiency, saving energy, reducing metal burning and decarburization of the forging surface and depletion of alloying elements;
(3) The multi-directional die forgings have no burrs, and the metal flow lines are distributed along the shape of the forgings, which avoids the exposed flow lines and improves the structure and performance of the forgings, especially the stress corrosion resistance;
(4) When the multi-directional die forging, the blank is deformed under compressive stress, which greatly improves the allowable deformation degree of the metal, which is especially important for difficult-to-deformed alloys such as high-temperature alloys with a low deformation temperature range.
Suitable for the production of large and extra large die forgings
According to the original work, it is possible to design and manufacture super-large hydraulic presses (currently 750 MN for large forging hydraulic presses), which is especially suitable for the production and production of large and extra large aluminum alloy and titanium alloy die forgings. At present, the maximum projected area of titanium alloy die forgings produced on hydraulic presses in the United States is 5.53 m2, and the projected area of forgings and screw presses such as forging hammers and screw presses is very difficult to reach lm2.
Suitable for the production of large reduction forgings
According to the characteristics of the hydraulic load, the energy characteristics and the length of the stroke, it is especially suitable for the extrusion process in which the load is almost constant over the long working stroke and the disc die forging which is mainly deformed by the machine. Other equipment cannot or Hard to do.
Not suitable for the production of thin forgings and large quantities of steel forgings
The hydraulic machine has a low freewheeling and loading speed, a low number of strokes per minute for continuous loading, and is difficult to achieve automation and mechanized production, and is not suitable for mass production of automobile die forgings.
Although the hydraulic machine has a certain anti-offset capacity, due to the low working speed and high temperature drop, it is generally not subjected to multi-die boring and is not suitable for the production of thin forgings such as blades.
It is worth mentioning that when the hydraulic machine is forged, the metal flows uniformly and stably under the action of low speed and static pressure. Therefore, the uniformity of the hydraulic forgings, the geometric size and the structure can be stabilized; in addition, the working speed of the hydraulic machine can be used forging steel. The mold helps to reduce the cost of forgings and shorten the manufacturing cycle.