Effect of Laser Action Parameters on the Formation of a Bath of the Molten B4C - Ti-6Al-4V Cermet Mixture
A. A. Golyshev, A. M. Orishich
Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch,, Russian Academy of Sciences, Novosibirsk, 630090, Russia
Keywords: laser cladding, CO laser, boron carbide, Ti-6Al-4V alloy, microstructure, microhardness, dimensionless parameters
Abstract
Results of a series of experiments aimed at studying laser cladding of individual tracks with the use of the B4C-Ti-6Al-4V cermet powder mixture are reported. The influence of laser cladding parameters (radiation power, beam motion velocity, and focus position) on the characteristics of tracks being formed (geometric sizes, microhardness, and elemental composition) is studied. It is shown that an increase in the concentration of reinforcing particles in the initial powder mixture alters the character of mass transfer inside the melt bath, leading to changes in the shape of the single track. It is found that a complex heterogeneous structure is formed in the melt bath, including secondary phase compounds formed in chemical reactions due to in-situ synthesis. The microhardness values at various points of the single track are observed to differ by more than a factor of 2 (in the interval HV0.3 = 548-1415).
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