TY - CONF A1 - Kautek, Wolfgang A1 - Daminelli-Widany, Grazia A1 - Krüger, Jörg ED - Meunier, M. T1 - Ultrashort pulse laser interaction with anodic metal oxide layers in electrolyte contact N2 - The removal and accelerated corrosion monitoring of metal coating systems is of general interest in materials science and engineering technology. The femtosecond and nanosecond laser ablation and delamination at 800 nm and 532 nm, respectively, of anodic oxide layers on aluminium alloys in electrolyte contact were investigated. Laser-induced modifications of the oxide layer resulted in an ionic contact between electrolyte and metal, which produced a current transient and thus allowed the in-situ electrochemical monitoring of the modification. Oxide coatings with different optical properties, almost transparent and opaque, were examined. The transparent anodic oxides showed contrasting ablation mechanisms in the nanosecond and femtosecond pulse duration regime: nanosecond pulses caused spallation, whereas femtosecond treatment led to ablation. Current signals measured in the transparent film were consistent with light absorption below the metal-oxide interface and with film spallation. Irradiation of the opaque coating yielded ionic current transients within the so-called shock-affected-zone of the oxide layer. This investigation provided insight into the role of the penetration depth of light and the heat-affected zone, the extent of the shock-affected zone, and the defect formation in the coating and at the solid-solid interface between metal and oxide. T2 - Symposium D - European Materials Research Society CY - Strasbourg, France DA - 2002-06-18 PY - 2002 UR - http://www.emrs-strasbourg.com/files/pdf/2002_SPRING/02_Prog_Dv2.pdf N1 - Serientitel: Applied surface science – Series title: Applied surface science VL - 208/209.2003,1 IS - 1 SP - 1(?) PB - Elsevier CY - Amsterdam AN - OPUS4-1731 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kautek, Wolfgang A1 - Daminelli-Widany, Grazia A1 - Cortona, Anna A1 - Kühnemund, Lutz T1 - Pulse laser electrochemistry - a novel approach for accelerated corrosion monitoring of lightweight alloys T2 - ECS Conference "Corrosion Problems in Industry" CY - Sharm El-Sheikh, Egypt DA - 2002-12-16 PY - 2002 AN - OPUS4-1998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kautek, Wolfgang A1 - Daminelli-Widany, Grazia A1 - Meja, P. A1 - Cortona, Anna A1 - Krüger, Jörg A1 - Autric, M. ED - Phipps, C. R. T1 - Femtosecond and nanosecond laser removal of anodic oxide layers from aluminium T2 - 4th SPIE's International Conference on High-Power Laser Ablation CY - Taos, NM, USA DA - 2002-04-22 KW - Laser ablation KW - Laser spallation KW - Microphone KW - Acoustical measurement KW - Aluminium oxide PY - 2002 SN - 0-8194-4524-X SN - 1605-7422 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series IS - 4760 SP - 239 EP - 246 PB - SPIE CY - Bellingham, Wash. AN - OPUS4-1551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kautek, Wolfgang A1 - Daminelli-Widany, Grazia A1 - Krüger, Jörg T1 - Femtosecond and Nanosecond Pulse Laser Electrochemistry of Aluminium Alloys T2 - 53th Annual meeting of the International Society of Electrochemistry CY - Düsseldorf, Germany DA - 2002-09-15 PY - 2002 SP - 1(?) PB - DECHEMA CY - Frankfurt a.M. AN - OPUS4-1586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kautek, Wolfgang A1 - Daminelli-Widany, Grazia T1 - Interfacial Processes during Pulse Laser Ablation of Oxides in Electrolytic Contact T2 - Bunsentagung 2002 ; Industrie-Symposium Industrielle Anwendungen der NMR: Struktur und Dynamik ; 101. Hauptversammlung der Deutschen Bunsen-Gesellschaft für Physikalische Chemie CY - Potsdam, Germany DA - 2002-05-09 PY - 2002 IS - 101 SP - 1(?) CY - Potsdam AN - OPUS4-1591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kautek, Wolfgang A1 - Rudolph, Pascale A1 - Daminelli-Widany, Grazia A1 - Krüger, Jörg T1 - Physico-chemical aspects of femtosecond-pulse-laser-induced surface nanostructures N2 - Near-ablation threshold investigations focusing on the generation of periodic nanostructures and their correlation with physico-chemical properties of the solid phase such as e.g., the material-dependent surface energy, were conducted. Molecular dynamic modelling in the sub-picosecond time domain was used to consider ultrafast opto-electronic processes triggering surface reorganization reactions. Fluid containment of solid interfaces showed strong influence on the resulting micro- and nanostructures due to its drastic reduction of the surface energy. The phenomena are discussed in respect to the minimization of the surface free energy in dependence of material composition and interfacial structure. PY - 2005 DO - https://doi.org/10.1007/s00339-005-3211-7 SN - 0947-8396 VL - 81 SP - 65 EP - 70 PB - Springer CY - Berlin AN - OPUS4-7403 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daminelli-Widany, Grazia A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Femtosecond laser interaction with silicon under water confinement N2 - Femtosecond laser interaction with silicon was investigated in water and in air, with 130-fs laser pulses at 800 nm wavelength. Under water confinement, higher modification thresholds, lower ablation depths and similar incubation factors were found in comparison to the dry experiment. Morphological features of the laser-induced cavities also differed. In contrast to air experiments, debris redeposition was negligible, while the ablated material remained suspended in the water layer phase. Underwater cavities obtained at high fluences and high number of pulses per spot showed anomalous profiles, consistent with a strong spatial deformation of the laser beam coupled into the target. Ripples formed at the edges of the modified area showed varying spacings: f100 and f700 nm for water and air experiments, respectively. Differences to the air experiment were related to a complex combination of fluence-dependent non-linear effects occurring in the water layer and to pulse-number-dependent shielding effects induced by cavitation bubbles and suspended ablated material. KW - Laser ablation KW - Silicon KW - Solid electrolyte interface KW - Water PY - 2004 DO - https://doi.org/10.1016/j.tsf.2004.04.043 SN - 0040-6090 VL - 467 IS - 1-2 SP - 334 EP - 341 PB - Elsevier CY - Amsterdam AN - OPUS4-4008 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daminelli-Widany, Grazia A1 - Pentzien, Simone A1 - Hertwig, Andreas A1 - Krüger, Jörg T1 - Influence of film thickness on laser ablation of hydrogenated amorphous carbon films N2 - Single-pulse damage thresholds of hydrogenated amorphous carbon (a-C:H) films were measured for 8-ns laser pulses at 532-nm wavelength. Layer thicknesses from below the optical penetration depth to above the thermal diffusion length (60 nm–13 µm) were examined. After correction of the damage-threshold values for the fraction of energy effectively absorbed by the material, the damage threshold was found to increase linearly with the layer thickness, also for film thicknesses below the optical penetration depth of a-C:H. The threshold fluence reached the bulk value for a layer thickness equal to the thermal diffusion length. The thermal diffusion coefficient was obtained from fitting the experimental data. Several phenomena like graphitization, blistering, exfoliation, and ablation were observed for different fluence regimes and film thicknesses. PY - 2006 DO - https://doi.org/10.1007/s00339-005-3460-5 SN - 0340-3793 VL - 83 IS - 1 SP - 89 EP - 94 PB - Springer CY - Berlin AN - OPUS4-12022 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -