Innovations in heat treatment with high power diode lasers

摘要

Using high power diode lasers for steel hardening is the kick-off for laser beam hardening in lots of industrial applications. The very high efficiency, the compact size and the shorter wavelength are advantages of high power diode lasers which are available up to 6 kW laser power. A new laser hardening system was developed to meet the industrial demands for a reproducible, economy-priced, and flexible laser hardening tool. It includes a High power diode laser, a cost-effective CNC-machine, a fast surface temperature control unit, and a special CNC-postprocessor. The base is a standard four-axis-milling-machine. Different lasers can be used. For instance we adapted a 2.5 kW-system with a flexible beam shaping unit. The surface temperature control unit tunes the laser power for a temperature accuracy oft 5 K at a selectable point of the laser spot. On-line control and storage of process data are possible if necessary for industrial applications. The CNC-postprocessor reduces the time for CNC-programming of components without CAD-data and a complicated shape. The postprocessor has an integrated look-ahead-function to change the feed rate as a function of heat outflow at convex and concave shaped components. The performance of this system will be shown at some industrial applications.