Surface structuring by laser remelting of 1.2379 (D2) for cold forging tools in automotive applications

Surface structuring by remelting with laser radiation is a new approach to shape metallic surfaces (“WaveShape”). In this structuring process, material is reallocated in its molten state instead of being removed, because the process is based on the new active principle of remelting. The surface structure and the microroughness result from a laser-controlled melt pool due to surface tension. Basic research has been conducted with promising results, especially for the hot work steel DIN 1.2343 (AISI H11) and the titanium alloy Ti6Al4V. This work is an attempt to expand the spectrum of processable materials, and the objective of this investigation is to determine the influence of crucial process parameters on characteristic surface features such as structure height for surface structuring by laser remelting of cold work steel 1.2379 (AISI D2). For the first time, an industrial laser polishing machine (“ALPINE”) was used for experimental investigations on surface structuring by laser remelting. The results achieved with this machine show that surface structuring by laser remelting is well suited to process the cold work steel 1.2379 (AISI D2) and that this industrial laser polishing machine is well suited to produce structured surfaces. In fact, for the first time, periodic surface structures with a structure height larger than 1 mm were created successfully using the WaveShape process.