Analysis of the influence of radiation polarization type on the absorptive capacity and propulsive motion of microparticles in the light field of СО2
laser
O.B. Kovalev
Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
E-mail: kovalev@itam.nsc.ru
Keywords: laser radiation, polarization, absorption, metal particle, vapor recoil pressure, light-propulsive force
Pages: 555–563
Abstract
The influence of the
linear and circular polarization of laser radiation on the absorption
coefficient of single spherical AISI-304 steel particles was theoretically
analyzed. It is shown that the absorbed power of the laser beam depends on the particle
sizes and on the location of particles in the light field. The influence of the
laser-induced evaporation of the material on the regularities of the reactive
motion of particles at a power density in the beam exceeding some
threshold value is established. The direction of the action of the reactive
force is directly related to the non-uniform distribution of the absorbed
laser-emitted power and with the recoil pressure of the vapors moving away from
the curvilinear surface of particle. A description to the mechanism of
deflection of the particle’s reactive force vector due to the vapor recoil
pressure in the light field of a Gaussian beam from the direction of the beam
action is given.
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