Thermoelectronic emission from the surface of aluminum with nanotubes under action of millisecond laser pulses is researched. Target (cathode) and collector (anode) were located in the vacuum camera (p ~ 10^-2 Pa) with quartz window, through which the laser ray was inserted. Cathode heating was carried out by YAG:Nd laser (λ = 1.06 μm , q ~ 10⁵ Wt/cm²) in the upward direction from the wire anode side. Cathode was made from Al with multilayer nanotubes. Al and mono-crystal Mo (100) were used as the standard samples. The temperature in Mo-target very center raised to 2990 K under this condition of laser irradiation.

It was found that the main way of electron emission from the cathode was that of thermoelectronic. The smallest amount of laser energy to start thermoelectronic emission was observed for Al with multilayer nanotubes and equaled 0.005 J. For aluminum without nanotubes it is equal to 0.4 J and for molybdenum - 0.8 J.

The samples were produced by inserting carbon nanotubes into aluminum matrix by Q-switched Nd-laser with flux density of energy 5·10⁸  - 2·10⁹ Wt/cm². Pressure pulses with duration regulated by the transparent condensed medium were generated.

Microstructure and chemical composition of the aluminum matrix surface with integrated nanotubes was studied by scanning electronic microscope with special block for the energy-dispersion microanalyses. Portion of the carbon varied from 5 % to 16 % and was not distributed homogeneously on the samples surface.

It was revealed that the current of thermoelectronic emission increases in two orders of that in aluminum surface with nanotubes compared with current from aluminum surface without nanotubes at the same parameters of millisecond-laser pulse action. The results of the experiments and its practical application have been analysed.

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