Spark plasma sintering treatment of cold sprayed materials for synthesis and structural modification: A case study using TiC-Cu composites

Materials obtained by cold spraying (CS) are subjected to post-spray treatment to increase cohesion between the particles. In this work, spark plasma sintering (SPS) was used for reactive processing of cold spray deposits for the first time. A mixture of a Ti-C-3Cu ball-milled powder and copper was used as a feedstock material for the formation of Cu matrix composites by CS. SPS treatment of CS deposits was used for the in-situ synthesis of TiC, formation of a dense structure and elimination of microcracks at the interface between the substrate and the deposit. The mechanism of structural changes in the composite agglomerates upon reaction was discussed. The TiC-Cu composite particles in the microstructure of the SPS-treated material possess a microhardness of 390 ± 40 HV_0.025, which makes them suitable as reinforcing elements of composite nature in the design of Cu matrix materials. This study shows that SPS treatment is a promising solution for post-spray processing of cold spray coatings.