Interfacial structure between particles in an aluminum deposit produced by cold spray

Aluminum deposit was produced by cold gas dynamic spraying technique. Due to the severe plastic deformation resulted from high speed impact, the spherical particles were deformed to be elongated splats. The microstructure of tangled area with interlaced thin strips was found at the outmost surface of particles, which contributes to the mechanical interlocking between particles. The microstructure evolution from the lamellar microbands with elongated subgrains to the newly formed refined area was observed at the region of particle boundaries. Corresponding to the various deformation conditions, such as nonuniform strain and geometrical effect, it shows a mixture of low and high angle boundaries between adjacent grains along the particle boundary, measured by convergent beam Kikuchi line diffraction.