Fig. 4: Nanoparticle-enabled prevention of spatter coalescence.
From: Controlling process instability for defect lean metal additive manufacturing
a–c X-ray images showing the spatter colliding induced agglomeration during the LPBF of Al6061. d The moving speed of Al6061 spatters. e–g X-ray images showing that two Al6061+4.4vol.%TiC spatters separated after colliding. h The moving speed of Al6061+4.4vol.%TiC spatters. i–k X-ray images showing the deformation of Al6061+4.4vol.%TiC spatters during colliding. The moving direction of the spatter is indicated by the white dashed arrow. l SEM image of the ball-milled Al6061+4.4vol.%TiC powder. m SEM image of the surface of the powder in l. n EDS analysis of Al6061+4.4vol.%TiC powder surface. o Nanoparticles prevented coalescence during spatter colliding. The blue dashed arrows represent the spatter moving velocity. p Schematic illustration of nanoparticle arrangement between two colliding Al6061+4.4vol.%TiC spatters. q Schematic illustration showing nanoparticles on spatter surface create a capillary pressure. r Comparison of inertial pressure and capillary pressure barrier as a function of temperature. Inset: The capillary pressure barrier between two colliding Al6061+4.4vol.%TiC spatters.
