Characterizations and anisotropy of cold-spraying additive-manufactured copper bulk

In this study, thick copper coatings were deposited by cold spraying (CS) as an additive manufacturing (AM) method. The interfacial microstructure evolution and mechanical behavior were investigated for the as-sprayed and annealed conditions. In addition, experiments together with numerical simulations were employed to study the recrystallization in different stages. Finally, the mechanical anisotropy of the CSed deposit was tested for the first time, being important to the applications of CS-AM. Results show that there exist two stages of recrystallization in the spraying and annealing processes. Heat treatment has a significant effect on mechanical properties, i.e., the tensile strength increases by 34.2% while microhardness decreases by 43.6%. The mechanical anisotropy analysis shows that the tensile strengths of different directions are completely different and show some regular changes.