Comparison of Heat Affected Zone due to nanosecond and femtosecond laser pulses using Transmission Electronic Microscopy

Ronan Le Harzic (1) , Nicolas Huot (1) , Eric Audouard (1) , Christian Jonin (1) , Pierre Laporte (1) , Stéphane Valette (1) , Anna Fraczkievic (2) , Roland Fortunier (2)

1 LHC - Laboratoire Hubert Curien
2 SMS-ENSMSE - Centre Science des Matériaux et des Structures

This letter presents a method aimed at quantifying the dimensions of the heat-affected zone ~HAZ!, produced during nanosecond and femtosecond laser–matter interactions. According to this method, 0.1 mm thick Al samples were microdrilled and observed by a transmission electronic microscopy technique. The holes were produced at laser fluences above the ablation threshold in both nanosecond and femtosecond regimes ~i.e., 5 and 2 J/cm2, respectively!. The grain size in the samples was observed near the microholes. The main conclusion is that a 40 mm wide HAZ is induced by the nanosecond pulses, whereas the femtosecond regime does not produce any observable HAZ. It turns out that the width of the femtosecond HAZ is less than 2 mm, which is our observation limit.

Domaines: Optique [physics.optics]

Ronan Le Harzic, Nicolas Huot, Eric Audouard, Christian Jonin, Pierre Laporte, et al.. Comparison of Heat Affected Zone due to nanosecond and femtosecond laser pulses using Transmission Electronic Microscopy. 2002. ⟨ujm-00118120⟩