Fabrication of Nanocrystalline metal films deposited by Supersonic Free-Jet PVD

We developed a new coating method named Supersonic Free-Jet PVD (SFJ-PVD). The SFJ-PVD is a technique to deposit nanoparticles with supersonic gas flow and to form a thick coating film. This method is composed of gas evaporation and vacuum deposition. The SFJ-PVD apparatus consists of evaporation chamber and deposition chamber. In the gas evaporation stage, a source material is evaporated to form nanoparticles in an inert gas atmosphere. The nanoparticles are then carried to a substrate with the inert gas through a transfer pipe where a gas flow is generated by the pressure difference between evaporation and deposition chambers. The gas flow is accelerated to supersonic velocity by a specially designed supersonic nozzle joined to the tip of the transfer pipe. In the vacuum deposition stage, the nanoperticles are deposited onto the substrate in the deposition chamber. We succeeded in obtaining a uniform nanocrystalline metal and ceramic films. The aim of our present work is to produce nanocrystalline thick films with the SFJ-PVD and to investigate mechanical properties of it.