What are the forging methods for titanium forgings?
November 05, 2022
The main methods applied to titanium forgings are free forging, open die forging (with burr die forging), closed die forging (without burr die forging), extrusion die forging, multi-directional die forging, division die forging, isothermal die forging, and their characteristics are as follows.
1, free forging
Free forging tools and equipment used in simple, good versatility, low cost. Compared with cast blanks, free forging eliminates shrinkage, shrinkage, porosity and other defects, so that the blank has higher mechanical properties. Forging simple shape, flexible operation. Therefore, it is particularly important in the manufacture of heavy machinery and important parts. Free forging, the processed metal in the upper and lower anvil iron between the deformation produced by pressure, in the horizontal plane of the direction of the metal can flow freely, so it is called free forging.
The equipment and tools used in free forging are more versatile, and the quality of forgings varies in size. However, the shape and size of free forging mainly rely on the forger's operating technology to ensure that the forger's high technical level requirements, high labor intensity, low productivity, low precision forgings, machining allowance is large, and can not get a more complex shape. So it is mainly used for single piece, small batch production and repair work. For large forgings, free forging is the only production method.
2, open die forging (burr die forging)
Open die forging is not completely restricted metal deformation flow in the die chamber, the mold with an excess metal to accommodate the fretting groove. At the beginning of die forging, the metal first flow to the die chamber, when the chamber resistance increases, part of the metal began to flow horizontally to the fretting groove to form a fringe. With the continuous thinning of the fringe and the lowering of the metal temperature there, the resistance of the metal to the flow of the fringe groove increased, forcing more metal into the die chamber. When the mold chamber is full, the excess metal from the fringe groove outflow.
3, closed die forging (no burr die forging)
Closed die forging, that is, no flash die forging, generally in the forging process on the die and the lower die clearance remains unchanged, the blank in the die chamber closed around the molding, does not produce transverse fringe, a small amount of excess material will form a longitudinal splinter, splinter in the subsequent process to remove.
4, extrusion die forging
The use of extrusion die forging, there are two kinds of extrusion die forging and reverse extrusion die forging. Extrusion die forging can manufacture a variety of titanium rings. Can obtain high geometric dimensional accuracy, the internal organization of the denser forgings. Extrusion die forging. Extrusion die forging has the common characteristics of extrusion and die forging, the basic process is similar to closed die forging, but the forged metal has a clear extrusion flow process and characteristics.
5、Multi-directional die forging
In the multi-directional die forging machine. Multi-directional die forging machine in addition to vertical punching plunger, there are two horizontal plunger, his ejector can also be used for punching, the ejector pressure than the ordinary hydraulic press ejector pressure is greater. Multi-directional die forging, the slide from the vertical and horizontal direction of the alternating joint action on the workpiece, with one or more perforating punch to make the metal from the center of the die cavity outward flow, in order to achieve the purpose of filling the die cavity. There is no burr on the parting line of the cylindrical piece for ordinary forgings.
6、Division die forging
In order to be able to forge large whole die forging parts on the existing hydraulic press, can be used segmented die forging, pad die forging and other divisions of the die forging method. Partial die forging method is characterized by the titanium cake section by section processing, each processing a part, so the required equipment tonnage can be very small. Generally speaking, this method can be used in medium-sized hydraulic presses to process large forgings.
7, isothermal die forging
Before forging, the mold is heated to the blank forging temperature, and in the entire die forging process mold and blank temperature to maintain the same, so that in the role of small deformation force to obtain large deformation. Isothermal die forging and isothermal superplastic die forging is very similar, the difference is that the latter in the die forging, the blank shall be superplastic treatment, so that it has a fine equiaxial grain.
