METHOD AND APPARATUS FOR LOW PRESSURE COLD SPRAYING

摘要

A cold spraying process for forming a coating of powder particles sprayed in a gas substantially at ambient temperature onto a workpiece is improved by placement in a low ambient pressure environment in which the pressure is substantially less than atmospheric pressure to accelerate the sprayed powder particles. The low ambient pressure environment is provided by a vacuum tank (16) having both the workpiece and a cold spray gun (12) located therein. The cold spray gun (12) is coupled to a source (30) of pressurized inert gas as well as to feeder (28) for providing a flow of the powder to be sprayed. The source (30) of pressurized gas is coupled to the cold spray gun (12) where it may be heated by passing through a heating coil (80) before being sprayed from a nozzle (40) onto the workpiece.