Pulse Shaping

Laser welding is both depending on material properties like temperature dependant reflectivity, heat conductivity or viscosity and on specific laser parameters like pulse energy, spot diameter or temporal pulse intensity.

In some cases the temporal shape of the laser pulse can have an influence on the welding quality. For example with highly reflective materials like silver or gold, the optical absorption of the material dramatically increases, when the temperature is raised near the melting point. In order to avoid over-heating of the material, specific pulse shapes can be used, which have a high laser intensity in the beginning and are then reduced in laser power, once the melting point has been reached.
Yet another effect that can be reduced by pulse shaping is the formation of fine cracks which can occur during quick cooling down of a weld and extreme material properties. Pulse shaping offers the possibility of fine tuning the laser for delicate tasks.
ROFIN lasers offer special pulse shaping menus, in which each pulse can be designed individually via an easy to operate graphic interface.

A pulse shape library, which consists of a number of pre-programmed pulses and plenty of storage space for individual solutions, assists an easy-to-switch operational mode.