Soldering is the 'whetting' joint of joining similar metals, IOW, the metals being joined do not experience any melting in the process.
Welding involves fusing (melting) the two metals together in some cases using a similar metal to provide the fusing process.
So no, you cannot weld by soldering.
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Welding and soldering are both forms of metal joining. They both use heat to fuse two pieces of metal together, but the process and results are quite different. So Can You Weld With a Soldering Iron? - ElectronicsHacks
The answer is complicated. We'll discuss the basics of welding and soldering, and give you some tips on how to get the best results if you’re trying to weld with a soldering iron.