EFFECT OF LASER IMPACT PARAMETERS ON THE FORMATION OF A POOL OF THE MOLTEN B 4 C — Ti–6Al–4V CERMET MIXTURE

Results of a series of experiments aimed at studying laser cladding of individual tracks with the use of the B 4 C–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 pool, leading to changes in the shape of the single track. It is found that a complex heterogeneous structure is formed in the melt pool, 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 HV 0.3 = 548–1415).