Die forging is divided into hammer forging and press forging.
The similarities between the two are:
(1) The die forging deformation process can be divided into three stages: the first stage is the squeezing stage, the second stage is the filling stage, and the third stage is the tying stage.
(2) The deformation process of the die forging can control the flow direction of the metal by providing the shape and dimensional change information of the material forming by the mold.
(3) The force-stroke curve is monotonously increasing, and the forming force reaches the maximum at the end of forging. The force-stroke curve of the die forging exhibits obvious phase characteristics, and the forming force increases sharply in the later stage.
The difference between the two is:
(1) When the hammer is forged, the flow and filling ability of the metal in the height direction is strong. When the press is forged on the press, the metal flows strongly in the horizontal direction;
(2) When the hammer is forged, the metal flows at a high speed, the friction coefficient is lowered, the inertia of the metal flow and the thermal effect of the deformation are prominent, and it is advantageous for forming the forging formed by the extrusion method. When forging on the press, the metal flow rate is slow and the inertia effect is not obvious. For the forgings formed mainly by the extrusion method, the multi-die boring is used to form the blank gradually.