Abstract: A electrostatic powder feeder includes a body having a cavity. The cavity is shaped and sized to hold a supply of powder particles and is defined by a cavity wall. A diverter is disposed in the cavity and positioned away from the cavity wall so as to create a powder flow space between the diverter and cavity wall. The feeder includes an electrode and a powder landing surface connected to a power supply. The electrode is positioned remotely from the powder landing surface at a distance at which it can act upon powder resting upon the powder landing surface. An aperture through which powder particles may fall is disposed in or proximate to the powder landing surface. An insulator is positioned between the electrode and the powder landing surface. The power supply produces an alternating electric potential that creates an alternating electric field between the electrode and powder landing surface that causes powder particles to oscillate and eventually fall through the aperture.

Abstract: A electrostatic powder feeder includes a body having a cavity. The cavity is shaped and sized to hold a supply of powder particles and is defined by a cavity wall. A diverter is disposed in the cavity and positioned away from the cavity wall so as to create a powder flow space between the diverter and cavity wall. The feeder includes an electrode and a powder landing surface connected to a power supply. The electrode is positioned remotely from the powder landing surface at a distance at which it can act upon powder resting upon the powder landing surface. An aperture through which powder particles may fall is disposed in or proximate to the powder landing surface. An insulator is positioned between the electrode and the powder landing surface. The power supply produces an alternating electric potential that creates an alternating electric field between the electrode and powder landing surface that causes powder particles to oscillate and eventually fall through the aperture.

Abstract: A electrostatic powder feeder includes a body having a cavity. The cavity is shaped and sized to hold a supply of powder particles and is defined by a cavity wall. A diverter is disposed in the cavity and positioned away from the cavity wall so as to create a powder flow space between the diverter and cavity wall. The feeder includes an electrode and a powder landing surface connected to a power supply. The electrode is positioned remotely from the powder landing surface at a distance at which it can act upon powder resting upon the powder landing surface. An aperture through which powder particles may fall is disposed in or proximate to the powder landing surface. An insulator is positioned between the electrode and the powder landing surface. The power supply produces an alternating electric potential that creates an alternating electric field between the electrode and powder landing surface that causes powder particles to oscillate and eventually fall through the aperture.

Abstract: A electrostatic powder feeder includes a body having a cavity. The cavity is shaped and sized to hold a supply of powder particles and is defined by a cavity wall. A diverter is disposed in the cavity and positioned away from the cavity wall so as to create a powder flow space between the diverter and cavity wall. The feeder includes an electrode and a powder landing surface connected to a power supply. The electrode is positioned remotely from the powder landing surface at a distance at which it can act upon powder resting upon the powder landing surface. An aperture through which powder particles may fall is disposed in or proximate to the powder landing surface. An insulator is positioned between the electrode and the powder landing surface. The power supply produces an alternating electric potential that creates an alternating electric field between the electrode and powder landing surface that causes powder particles to oscillate and eventually fall through the aperture.

Abstract: A method for detecting a subsurface defect in a workpiece undergoing processing includes directing focused heat energy from an energy point source on to the workpiece to generate a melt pool and cause a solid portion of the workpiece to emit incandescent radiation. The incandescent radiation emitted by the solid portion of the workpiece is captured and a signal based upon the color or intensity of the captured incandescent radiation is output. A processor receives the output signal and analyzes it for any variance. If any variance is detected, the region associated with the variance is determined. In this fashion, gradients in the color or intensity distribution reveal subsurface defects.