The short answer is yes, as long as you use the correct heat source, solder, and flux.
When soldering stainless steel, you cannot use normal soldering flux. No-clean and Rosin fluxes will not work on stainless steel. You will need a more powerful high activity acid flux because of the greater amount of oxides on the surface of stainless steel. These oxides are what prevents the solder from sticking to the surface.
You will need silver bearing solder along with the high activity flux specifically designed for stainless steel. Once you have both of these, the process is very similar to regular soldering. Some silver-bearing solders contain an acid flux core but that is not always enough flux to get the job done. In these cases, you will need to add more flux to the joint to solder stainless steel.
Small wires and some jewelry items can be successfully soldered with an iron, but any larger items would require a torch. The type of torch needed depends on the size of the parts you are trying to solder. If they are too large to adequately heat using a soldering iron, you can opt to use a small butane torch like the popular Blazer GB2001. The next size up would be the Blazer Big Shot, which produces a much larger flame and is suitable for plumbing and automotive work.
For larger industrial applications, you could use a propane, oxy-acetylene, or map gas torch. To learn more about hydrogen torches, check out our detailed guide on them here.
