TY - CONF A1 - Gornushkin, Igor B. A1 - Veiko, V. P. A1 - Karlagina, J. J. A1 - Polyakov, D. S. A1 - Samokhvalov, A. A. T1 - Reverse deposition of TI-oxides under nanosecond laser ablation of TI N2 - Processes of laser induced oxidation of metals are typically studied in the framework of heterogeneous chemical reactions occurring on the irradiated surface, which lead to the formation of dense oxide films deposited on it. Such technology has many applications like color-laser marking technology and laser recording on thin metal films for creation of diffractive optical elements . Under the conditions of strong laser ablation, another oxidation mechanism becomes possible: evaporated atoms react with oxygen in a surrounding atmosphere and the products of such reaction are redeposited back onto the substrate. The chemical and phase composition of such deposited layer, its density, morphology and structure depend on the conditions of laser ablation. By varying these conditions, the main properties of such coating can be controlled that is important for some potential application (for example in biomedicine). In our report we present the study of the processes of redeposition of oxides structure under the conditions of multipulse nanosecond laser ablation of titanium (Grade 2) in air atmosphere at normal conditions. Our experiments show that titanium-implants with such deposited oxide layer have increased biocompatibility. Modelling of chemical reaction in laser-induced plasma coupled with experimental methods of plasma optical emission spectroscopy allows us to determine the types of main chemical reactions in laser plasma as well as it influences on the plume dynamics and vapor condensation kinetics. As a result, we propose the general physical picture of reverse deposition of oxides structure under the condition of strong nanosecond laser ablation. The formation of the titanium oxide precipitate is explained not only by collisions in the plasma, but also by the chemical interaction of titanium and oxygen, which leads to the formation of а low pressure area near the substrate and additionally stimulates the reverse deposition of oxides. We expect, similar processes are valid not only for titanium but also for other metals and, possibly, semiconductors. T2 - 28th International Conference on Advanced Laser Technologies CY - Online meeting DA - 06.09.2021 KW - Laser ablation KW - Laser induced plasma deposition KW - Surface coating KW - Emission spectroscopy KW - Titanium dioxide KW - Hydrodynamic model KW - Plasma chemistry PY - 2021 AN - OPUS4-53245 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -