Direct-metal-deposition (DMD) nozzle fault detection using temperature measurements

This invention relates generally to additive manufacturing and, in particular, to nozzle configurations, and methods of use, in conjunction with laser-based direct metal deposition. The temperature of the deposition tip in a direct metal deposition (DMD) apparatus is monitored to circumvent problems due to tip clogging. Both the inner and outer nozzle tips are monitored utilizing appropriate sensors, which are interconnected to a controller programmed to detect a predetermined rise in tip temperature. If an unacceptable condition is sensed, the equipment may be configured to sound an alarm, display a warning condition, or enter a controlled shut-down of the deposition apparatus. Use of the invention accordingly permits the detection of even partial clogging when it occurs, allowing an operator to take immediate corrective measures both to protect the nozzle from damage and to insure the highest possible deposition quality.