Abstract
Time-resolved thermographic measurements were performed by a high speed infrared camera on a substrate surface during cold gas dynamic spraying without powder particles. Experiments were carried out on three commercial cold spray systems (Centerline SST, CGT Kinetiks 3000 and Inovati KM-CDS 2.2) spanning a wide range of gas pressures, gas temperatures, gun traverse speeds and stand-off distances. The substrate surface temperatures were measured directly beneath the cold spray gun nozzle as well as at predetermined distances from the gun giving a general evaluation of the heat input to the substrate in actual deposition conditions. It is shown that the substrate surface temperature can rise to a value close to the inlet gas stagnation temperature in the area located beneath the cold spray gun (bow shock region). For the same set of process conditions, significant differences were found in measured surface temperature range between the three cold spray systems, due to differences in nozzle configuration.