Rapid densification of cold-sprayed Ti–6Al–4V coatings via induction heating

Cold spray is a promising solid-state additive manufacturing technique for depositing Ti-6Al-4V alloy. However, due to the alloy’s high strength, the resulting coatings are often porous. While vacuum furnace heat treatment can effectively reduce porosity, it is time-consuming, typically requiring several hours. In this study, a rapid post-processing method using induction heating was investigated. Cold-sprayed Ti-6Al-4V coated samples were subjected to induction heating at 900 ˚C, 1000 ˚C and 1100 ˚C for 10 minutes. The treatment significantly reduced the coating porosity from 3.1% to 1.2%. The treatment also improved interfacial bonding of the coatings and flexural strengths of the samples. The enhancements are attributed to the athermal effects of eddy current, which promotes preferential localized Joule heating and enhances atomic diffusion around the pores. This work demonstrates the potential use of induction heating as a fast and effective post-processing method on cold-sprayed Ti-6Al-4V coatings.