D.H. Lammlein PhD Dissertation - Vanderbilt University

setting are indicated. Note that strength continues to increase with depth beyond the
matrix depth of 0.10” despite distortion at the base of the joint (see Figure 119 and Figure
120). ................................................................................................................................ 134
Figure 119: Macrosection view of an unsupported, butt configuration weld made with a
100º conical tool (0.025” diameter snub-nose and 0.015” cupped nose recess) at 800rpm,
5.2 ipm, and a penetration depth of 0.11”. ...................................................................... 135
Figure 120: Macrosection view of an unsupported, butt configuration weld made with a
100º conical tool (0.025” diameter snub-nose and 0.015” cupped nose recess) at
1000rpm, 10.4ipm, and a penetration depth of 0.11”. At this depth, unsupported welds
made with the conical tool begin to split and protrude at the root for some of the tested
weld parameters. The initiation of protrusion and splitting in the weld root at 0.110” was
deemed undesirable by the authors for the suggested applications. The experimental
matrix was therefore performed at 0.100” where this did not occur. It should be noted
however that the strength of the unsupported welds increased with depth beyond the
experimental matrix depth of 0.100”. ............................................................................. 135
Figure 121: Surface appearance of an unsupported, butt configuration weld made with a
100º conical tool (0.025” diameter snub-nose and 0.015” cupped nose recess) at
1000rpm, 10.4ipm, and a penetration depth of 0.11” (1/16 th inch demarcations). ........ 136
Figure 122: Conical tool, unsupported, partial penetration welds were performed at four
depths at the 10.8ipm and 1000rpm parameter setting and showed a consistent increase in
axial force with penetration depth. .................................................................................. 137
Figure 123: Weld moment was a better indicator of penetration depth for the conical tool
and a torque based control method was used in the experiment to maintain penetration
depth. ............................................................................................................................... 138
Figure 124: (threaded tool) Tetrahedral mesh created in the Fluent preprocessor Gambit.
......................................................................................................................................... 139
Figure 125: (threaded tool) Geometry ............................................................................ 140
Figure 126: (threaded tool) Contours of temperature in degrees Celsius. ...................... 141
Figure 127: (threaded tool) Contours of temperature in degrees Celsius. ...................... 142
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