D.H. Lammlein PhD Dissertation - Vanderbilt University

Figure 156: Macrosections of selected welds made with the wide probe tool.
A FLIR thermal camera was used to make thermal videos of the full weld cycle.
The camera was calibrated to the emissivity of the tool shank. Figure 157 shows a
thermal image from thermal video taken during the experiment showing the region of
interest on the tool shank. The curved outer surface of the aluminum pipe sections were
too reflective to give reliable emissivity calibration, thus the tool shank was used. Figure
158 shows the average tool shank temperature over the steady state portion of welds
made using the narrow probe tool and Figure 159 shows the corresponding data for welds
made with the wide probe tool. The charts show shank temperature decreasing
predictably with increasing traverse rate. Higher rotation rates generally resulted in
higher temperatures but this relationship was not as consistent in the data. The charts
show the wide probe welds to be slightly hotter than the narrow probe welds. The
experimental shank temperature agrees closely with the CFD model results at the
modeled parameter (1000rpm, 5.2ipm) for both geometry cases.
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