Comparative analysis of the effect of CO2 laser radiation on light propulsion acceleration of powder particles during the laser cladding

The problems of measuring the velocity and temperature of particles in the light field of a constant and pulsed-periodic CO₂ laser are solved using noncontact methods of registration based on a spectrometer and a complex of laser and optical means. The purpose of this research is analysis of the influence of the laser radiation on particles transport during the laser cladding. The powders of alumina, molybdenum, nickel, aluminum with standard for the laser cladding technology size distribution of particles were used. Air, nitrogen, argon were used as process gases. The СО₂-laser working both in continuous and pulse-periodical modes, with the average power up to 2 kW and pulse power of dozens/hundreds kW was used as the radiation source. It is demonstrated that in the laser radiation field, the powder particles get an extra acceleration due to the evaporation and reactive force resulting from the recoil pressure of vapors from the evaporable surface of particles.

A comparative analysis of the measured parameters of particles (velocity and temperature) in the light field of a constant and pulsed-periodic CO₂ laser in a coaxially transporting, jet gas-dispersed flow is presented.