Research at the European XFEL: Materials imaging and dynamics research on laser peening

Laser peening is a surface treatment technique that improves the mechanical performance of metals. It can be used to increase material’s resistance to crack initiation, extend fatigue life and to enhance fatigue strength. Most studies of laser peening used nanosecond pulsed lasers, which require a sacrificial coating and a transparent overlay. Femtosecond laser peening without a protective coating was reported recently, which makes this new process technologically very attractive. During this experiment at European XFEL’s Materials Imaging & Dynamics instrument (MID), Andras Borbely from MINES Saint-Etienne in France conducted in situ characterization of the peening process. The data was used to corroborate a realistic model, which takes into account electromagnetic absorption with two-temperature hydrodynamics and shock wave propagation.