The kinetics of formation of interparticles contacts during laser sintering of metal powders

Regularities of processes of bonding the particles of single-component metallic (Ni alloy) powders in their laser sintering are investigated experimentally. It is ascertained that the formation of interparticle contacts includes following steps: surfacial fusion of particles under heating; migration of melt surface layers with formation of liquid rings in the near-contact region; melt solidification under cooling with forming the crystalline interparticles necks. Process duration and microstructure of powdered layers are investigated depending on laser radiation energy density.