Abstract: The powder injection system consists of a dosage chamber directly fed by a conventional powder feeder and communicated with barrel of the detonation gun through a direct conduit. In this way, the pressure wave advancing through barrel enters the communication conduit and upon reaching dosage chamber undergoes a sudden expansion, interrupting powder feeding from the continuous feeder and causing the full fluidization of powder contained in dosage chamber. The fluidized powder is suctioned to barrel where it remains until the pressure wave generated in a new detonation cycle carries it away, depositing it on the surface of the part to be coated.