In modern manufacturing processes laser heat treatment is used to modify local surface properties or to optimize the shape of components. For reliably reaching the desired property profiles it is crucial that the optimum process temperature is reached at every point of the processed surface. Especially components with high variations of the local heat dissipation capability due to edges, radii, grooves, drill holes or varying wall thicknesses make the controlled generation of a homoge-neous or application-optimized temperature field extremely difficult and require continuous ad-justment of the laser intensity fields. It might be possible to identify the necessary process parame-ters over the course of one or several test runs. However, this is time-consuming, susceptible to changes in process conditions and, in case of low volume productions or one-offs, uneconomical or simply impossible.

Dynamic beam shaping of the laser using scanning technologies in combination with spatially re-solved temperature measurements and real-time process control offers an optimal solution for this problem. Automatically adjusting scan patterns, scan speeds and laser power it is possible to re-spond to local changes in heat dissipation within milliseconds and thereby preventing a drift of the local temperatures.

The possibilities offered by dynamic beam shaping are demonstrated by numerical simulation of laser heat treatment processes of tool steel using harmonic 2D-scan functions with and without modulation of the laser power. The results were verified using a new, compact single-mirror-system with AI path-control. Application examples of laser heat treatment processes (hardening, tempering, normalizing) will be shown.