Laser Beam Hardening in Tool Making

Local laser beam hardening of cutting dies and moulds for car body-in-white parts has become a widespread technology. The Fraunhofer IWS systems allow optimum and reliable processes due to the process control and the generation of optimized laser spot shapes and intensity profiles. These systems are applied, for instance, in a robot based laser hardening and cladding machine within the tool shop at Audi AG Ingolstadt and at Volkswagen AG in Wolfsburg.

The challenge of this development was the necessity of an optimum process result without making the usual geometrical optimization loops. The dynamic laser beam shaping system "LASSY" has been applied, so that for each contour to be hardened a laser spot can be generated with an appropriate width and intensity profile. During an ongoing laser hardening process, changes can be made by commands of the CNC program. Process control is performed with the "LOMPOCpro" control. The temperature is measured with the integrated camera system "Emaqs". 60 mm wide hardening tracks are possible with the available 6 kW laser power. For the adaption of these systems to a robot, robust and pivoting process modules have been developed. These modules enable a good accessibility to the tool contour as well as a fast alternation of the technologies hardening and cladding.