In addition to friction welding, there's another production method that exploits heat from friction to perform operations in metal: Thermal drilling.
With thermal drilling, a conical bit is rotated at high speed and driven into sheet metal or the walls of metal tubing. The heat generated deforms the material at the point of contact, allowing the bit to push through. But what's especially neat here is that material is not excavated, as with drilling a hole with a conventional twist bit; instead the heated material is actually formed into a bushing within the workpiece itself, providing a convenient mounting point for a fastener. And yes, it can be tapped.
Check out this video demonstraiton, put together by thermal drilling company Formdrill USA:
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