Reactive spray formation of coatings and powders

A method for spraying a reactive fluid feedstock, the method comprising

• providing a conduit having a first end and a second end respectively including an opening port and an exit port, the size of the exit port being smaller than the size of the opening port, the second end forming or associated with a tapered nozzle,
• heating a reactive feedstock to a supercritical temperature in a volume distinct from the volume of the conduit and then passing the reactive feedstock under pressure through the conduit from the opening port to the exit port and through the tapered nozzle to create a feedstock spray,
• providing a chamber enclosing the conduit, the chamber being in communication with a source of an auxiliary gas and with the exit port,
• passing an auxiliary gas through the chamber into the feedstock spray, said auxiliary gas and said feedstock spray turbulently mixing within the chamber;
• and
• igniting the turbulently mixed feedstock and the auxiliary gas spray resulting in a reactive fluid flame spray at the exit port.