The influence of pulsed CO2-laser radiation on the transport of powder during laser cladding of metal
Tóm tắt
The problem of measurement of the in-flight velocity and temperature of particles in the light field of a pulsedperiodic laser was solved using contactless detection methods. The solution of the problem is based on using a spectrometer and a complex of laser and optical means. The diagnostic technique combines two independent methods for measuring the in-flight particle velocity: a passive one, based on the registration of the natural radiation emitted by the heated particles in the gas flow, and an active one, using the effect due to laser-beam scattering. Histograms of the statistical distributions of particle velocities for two operating modes of a coaxial nozzle were presented. There is no laser radiation in the first mode. There is pulsed laser radiation in the second mode. In the experiments, various powders (Al2O3, Mo, Ni, Al) with particle size distributions typical of laser deposition technology and various working gases (air, nitrogen, argon) were used. СО2-laser works in pulse-periodic mode with a mean power up to 2 kW. Pulsed power reaches several ten/hundred kilowatts. It is shown that in the field of laser radiation, powder particles acquire additional acceleration due to the evaporation and the appearance of a reactive force due to the recoil pressure of the vapors emitted from the irradiated part of the particle surface. It is shown that laser radiation can significantly affect the velocity and temperature of powder particles being transported by a gas jet. At the maximum carrier-gas velocity of up to 30 m/s, the velocities of single particles due to the laser-induced acceleration can reach the values of the order of 120 m/s.
Tài liệu tham khảo
D. Lepski and F. Bruckner, Laser cladding, in: The Theory of Laser Materials Processing (Heat and Mass Transfer in Modern Technology) / J.M. Dowden (Ed.). Springer Series in Material Sci. 119, Springer, 2009, P. 235–279.
V.P. Lyagushkin and O.P. Solonenko, A method to simultaneously measure the velocity and temperature of disperse particles in high-temperature flows, in: Proc. 7th Int. Symp. on Plasma Chemistry, Eindhoven, Netherlands, 1985, vol. 3, p. 730–735.
G. Mauer, R. Vaben, S. Zimermann, T. Biermordt, M. Heinrich, J.-L. Marques, K. Landes, and J. Schein: Investigation and comparision of in-flight particle velocity during the plasma-spray process as measured by laser dopler anemometry and DPV-2000, J. Thermal Spray Technol., 2013, vol. 22, no. 6, p. 892–900.
F. Meriaudeau, E. Renier, and F. Truchetet, CCD technology applied to laser cladding, Proc. of SPIE, 1996, vol. 2654, p. 299–309.
H. Tan, F. Zhang, R. Wen, J. Chen, and W. Huang: Experiment study of powder flow feed behavior of laser solid forming, J. Optics & Laser in Engng., 2012, vol. 50, p. 391–398.
F. Zhang, J. Chen, H. Tan, X. Lin, and W. Huang: Composition control for laser solid forming from blended elemental powders, J. Optics & Laser Technology, 2009, vol. 41, p. 601–607.
F. Meriaudeau, F. Truchetet, D. Aluze, and C. Dumont: Machine vision system applied to the characterization of a powder stream: application to the laser cladding process, Proc. SPIE, 1998, vol. 3306, p. 22–31.
W. Liu, B. Xu: Sh. Dong, and Sh. Yan, Characteristic analysis of the gas-powder stream for laser cladding, in: Proc. FISITA 2012 World Automotive Congress Lecture Notes in Electrical Engng, 2013, vol. 199, p. 99–107.
F. Meriaudeau and F. Truchetet: Image processing applied to laser cladding process, Proc. SPIE, 1996, vol. 2789, p. 93–103.
F. Meriaudeau, E. Renier, and F. Truchetet, CCD technology applied to laser cladding, Proc. SPIE, 1996, vol. 2654, p. 299–309.
F. Meriaudeau, F. Truchetet, and C. Dumont: High-speed photography applied to laser cladding, Proc. SPIE, 1997, vol. 2869, p. 994–1003.
V. Kebbel, J. Geldmacher, K. Partes, and W. Juptner: Characterization of high-density particle distributions of optimization of laser cladding processes using digital holography, Proc. SPIE, 2005, vol. 5856, p. 856–864.
J.S. Goela and B.D. Green: Ablative acceleration of small particles to high velocity by focused laser radiation, J. Optical Soc. America B, 1986, vol. 3, no. 1, p. 8–14.
S.D. Zakharov, M.A. Kazaryan, and N.P. Korotkov: Shock acceleration of particles in a laser beam, JETP Lett., 1994, vol. 60, no. 5, p. 322–324.
I.O. Kovaleva and O.B. Kovalev: Simulation of the acceleration mechanism by light-propulsion for the powder particles at laser direct material deposition, J. Optics & Laser Technology, 2012, vol. 44, p. 714–725.
D.V. Sergachev, A.A. Mickhal’chenko, O.B. Kovalev, V.I. Kuz’min, G.N. Grachev, and P.A. Pinaev: Laseroptic measurement of velocity of particles in the powder stream at coaxial laser cladding, Physics Procedia, 2014, vol. 56, p. 193–203.
V.I. Nalivaiko, P.A. Chubakov, A.I. Pokrovskii, A.A. Mikhal’chenko, V.I. Kuzmin, and E.V. Kartaev: Smallsize spectrometer for emission analysis of low-temperature plasma flows, Thermophysics and Aeromechanics, 2007, vol. 14, no. 2, p. 247–256.
A.A. Mikhal’chenko, V.I. Kuzmin, D.V Sergachev, E.V. Kartaev, I.S. Ivanchik, and S.N. Ivanchik: The heating and acceleration dynamics of Al2O3 particles in the axisymmetric heterogeneous flow emanating from a plasma torch with interelectrode inserts, Thermophysics and Aeromechanics, 2014, vol. 21, no. 4, p. 515–527.
O.P. Solonenko, A.A. Mikchal’chenko, and E.V. Kartaev, Measuring velocity, surface temperature and size of single particle in pasma flow based on 3-color pyromtery, in: Proc. 5th JSME-KSME Fluids Engng Conference, Nagoya, Japan, 2002, 5 p. (CD).
P.A. Statsenko, G.N. Grachev, A.L. Smirnov, and A.A. Myakushina: Study of the spatial characteristics of emission of a high-power CO2 laser generator-amplifier system, Proc. of the 22-nd Int. Conference “Lasers. Measurements. Information. 2012”, St.-Petersburg, 2012, vol. 2, p. 168–176.
V.I. Kuz’min, A.A. Mikhal’chenko, O.B. Kovalev, E.V. Kartaev, and N.A. Rudenskaya: The technique of formation of the axisymmetric heterogeneous flow for thermal spraying of powder materials, J. Thermal Spray Technol., 2012, vol. 21, p. 159–168.
G.V. Saidov and O.V. Sverdlova, A Practical Guide to Molecular Spectroscopy. Students’ manual, N.G. Bakhshiyev (Ed.), Leningrad University, 1980.
A.N. Magunov, Spectral Pyrometry, Fizmatlit, Moscow, 2012.