I still haven't been able to find any more background. I did find that this type of work is characterized as "tig art", and this process is technically known as "hardfacing" or "hardsurfacing".

There's also a now-deleted arronexus Instagram account with tig art, and you can pinterest around for "tig art" to find more examples. However, the ones I saw, though interesting, were not of this same weld quality.