Laser cleaning of insect residue with a TEA-CO2 -laser in shockwave regime

Nowadays, much effort is put into the development of laminar flow technologies for next generation aircrafts creating laminar flow in areas around the leading edge of wings of an airplane. Laminar flow reduces drag at aero plane wings thus reducing environmental pollution and costs due to saved kerosene. Nevertheless, three dimensional disturbances like insect residues, if reaching a threshold height, cause a breakdown in laminar air flow turning it into a turbulent one. Consequently, these insect residues need to be removed repeatedly. Therefore, insect residues were artificially applied on 1.4544.9 steel and Titanium Grade 5 and removed using a TEA-CO ₂ laser in multiple cleaning cycles. The cleaned area was investigated in terms of process influence on the base material using micro hardness measurements, CLSM and SEM imaging of the topography and grain structure. This paper presents a way of significantly reducing (by 84%) the inhomogeneously distributed insect residue without any identified alteration of the base material regarding hardness, topography, or grain structure.