Product Code: ICAL05_1306

Measuring Laser Absorption and Powder Capture Efficiency During Deposition
Authors:
Aaron Costello, South Dakota School of Mines & Technology; Rapid City South Dakota USA
Kate Nelson, South Dakota School of Mines & Technology; Rapid City South Dakota USA
Tricia Krungjohn, South Dakota School of Mines & Technology; Rapid City South Dakota USA
James Sears, South Dakota School of Mines & Technology; Rapid City SD USA
Michael Langerman, South Dakota School of Mines & Technology; Rapid City South Dakota USA
Umesh Korde, South Dakota School of Mines & Technology; Rapid City South Dakota USA
Presented at ICALEO 2005

There have been considerable modeling efforts aimed at studying the thermal response and residual stresses produced during Laser Powder Deposition. However, there has been little published on quantifying the laser energy transfer during Laser Powder Deposition. The energy transfer measurement is critical for producing accurate estimate of the thermal response and residual stresses produced. In this study a calorimeter was design and built as part of a Mechanical Engineering Department Senior Design Project at the South Dakota School of Mines and Technology. The results were obtained for absorption while delivering 316L SS powder onto a stainless steel tube at various laser powers and powder delivery rates. In conjunction with the absorption measurements, powder capture efficiency was also measured as a function of laser power. This study was conducted while using a 3 kW Trumpf Nd:YAG laser configured with a Precitec annular powder feed nozzle.