Upset ratios in laser-based free form heading

A laser-based micro upsetting process is presented which takes advantage of scaling effects in order to optimize the conventional multi-stage upsetting. Due to the fact that the surface tension exceeds the gravitation force with increasing miniaturization, in the micro-range an accumulation of molten material forms a nearly perfect sphere, which can be finally formed in a secondary process step. It is shown that the laser-based free form heading process improves the upset ratio up to 45 instead of 2.3 commonly achieved by conventional multi-stage upsetting processes.