Electric assistance hot incremental sheet forming: an integral heating design

The electric assistance incremental forming technology is usually adopted to form hard-to-form sheet metals. Recently, the local heating method by current is used to fabricate specimens with these materials due to low costs and simple setups. However, the heating method has four natural defects: inhomogeneous temperature distribution, arc burns for the sheet and the tool, unsuited for multistage forming, and complex lubrication processes. In this work, a novel heating design, directly making current flow from the one side of the sheet into the other side of the sheet, was proposed to form specimens with TC4 Ti alloy. Meanwhile, different current values were adopted in numerical simulation and experiments, which demonstrated that a current value of 500 (A) should be selected to fabricate the specimen with TC4 Ti alloy. In addition to this, some forming results, such as temperature variations, roughness, and tool damage, obtained respectively by local and integral electric heating incremental forming processes were analyzed further.