Computer Simulation to Predict Load, Stress, and Metal Flow in an Axisymmetric Closed-Die Forging

Abstract

The design of a closed-die forging process requires the estimation of maximum forging load and the necessary forging energy. To determine the forging energy, the forging load at various stroke positions must be estimated.

In the past, empirical methods have been used with varying degrees of success. The present study attempts to predict the forging load and stresses through relatively basic analytical methods. Using the example of an axisymmetric forging, consisting of a flange and a shaft, the slab or Sachs method has been applied to develop a computer-simulation technique. The forging process is analyzed in small steps of deformation. The stress distribution, the load, and the magnitude of filling of the die and the flange have been estimated at each deformation step. The theoretical predictions have been compared with experimental results in forging the part from both lead and aluminum to various stroke positions with a hydraulic press.

The computer program simulating the axisymmetric forging process, applied to an example in the present study, can be extended to other shapes and be used for various billet sizes, part dimensions, temperature, ram speeds, and friction. conditions.