Experiments and analysis of the effect of local induction heating on deformation

In hot forming processes the billet is usually placed in a furnace and heated to a constant temperature. It is important to examine the need to through-heat the billet where the level of deformation varies from one section to another. For example, in forging a large workpiece, it is not possible to effect plastic deformation to the overall volume of the workpiece due to the extremely high load that would be required to perform the operation. Therefore, operating on small sections, aided by partial heating, enables the deformation to take place with a considerably reduced forming load. This paper examines the use of differential heating, and in particular the application of induction heating, to effect deformation locally. The term differential heating is used here to describe processes where the billet is locally heated at various locations, irrespective to its size, prior or during the loading cycle. Application and requirements for analytical approaches using finite element have been investigated with some comparison with laboratory experiments.