On the characterization of bulk copper produced by cold gas dynamic spray processing in as fabricated and annealed conditions

Highlights: → Demonstrated feasibility of cold gas dynamic spray as a freeform fabrication process. → Microstructural analysis of heavily cold worked metal powders. → Mechanical property evaluation of cold gas dynamically sprayed bulk material. → Assessment of strengthening due to deformation and subsequent annealing on cold sprayed metals. - Abstract: The use of cold gas dynamic spray processing (cold spray), a process known for a coating and repair process for many alloy systems, has been demonstrated for the production of bulk copper deposits exceeding 25 mm in thickness. The microstructure and hardness of the specimens were characterized in as sprayed and annealed conditions. Microhardness was measured in both directions from the spray/substrate interface to assess the effects of cold spray impact on the substrate material and to characterize the properties of bulk 'as-sprayed' copper before and after annealing. Microstructure was analyzed via scanning and transmission electron microscopy.