Hybrid Additive Manufacturing Technology: Induction Heating Cold Spray—Part I: Fundamentals of Deposition Process

The prevention of delamination of soft and ductile materials from hard substrates is a challenge when using the cold spray process. As a potential solution to this issue, a tunable hybrid additive manufacturing process was developed by coupling induction heating and cold spray processes. Pure aluminum was used as the soft feedstock powder, while Ti-6Al-4V was used for the hard substrate. The effects of induction heating and of the substrate initial temperature on the deposition process were evaluated. Single-particle impact tests suggested metallic bond formation at the particle/substrate region as the bonding mechanism. Deposition efficiency, coating thickness and porosity levels were evaluated to characterize the induction heating and initial substrate temperature effects. The deposition efficiency and the coating thickness were doubled with the hybrid additive manufacturing process compared to the traditional cold spray process. Moreover, the presence of eddy currents in the coating (in situ induction heating of the coating) was confirmed by an electromagnetic analysis which modeled the interaction between the coating and the electromagnetic field. Findings demonstrated that substrate preheating has little influence on the overall deposition process and coating quality compared to in situ induction heating effects.