Surface structuring of metals with short and ultrashort laser pulses

In recent years industry has shown a growing interest in the field of micro-structuring of surfaces on macroscopic workpieces. Several applications to improve the tribological properties of surfaces are known as well as various techniques for printing and embossing. First industrial applications use pulse durations of nanoseconds or longer. However, the quality of the resulting structures is limited due to the formation of recast that has to be removed by additional post-processing. Experimental results have shown that it is possible to avoid recast formation by shortening the pulse duration into the femtosecond regime when low energy density values are used. Detrimental is the fact that process speed with available laser systems is low compared to nanosecond processing. This contribution will show and discuss results in the field of surface structuring of metals with laserpulses in the range from nanoseconds to femtoseconds. The final decision between nanoseconds and femtoseconds has to be made for each specific application.