Optical sensor to monitor and control temperature and build height of the laser direct-casting process.
A nonintrusive optical sensor system is applied to real-time process control of the recently developed laser direct-casting process, in which a stream of metal powder is introduced into the beam of a high-power (500-W) cw laser to fabricate complex three-dimensional structures. The sensor system allows two critical parameters, temperature and build height, associated with this process to be monitored and controlled continuously. We achieved a height-sensing resolution of ?0.25 mm and temperature control with a resolution of ?10 degrees C at a typical working temperature of 1500 degrees C with an evident improvement in process quality, especially for complex workpieces comprising relatively high, thin walls at which the conductive heat transfer varies substantially as the process proceeds.
Fox
M D
MD
Hand
D P
DP
Su
D
D
Jones
J D
JD
Morgan
S A
SA
McLean
M A
MA
Steen
W M
WM