No, plumbers' putty should not be used on stainless steel. Plumbers’ putty is designed for use with porcelain, ceramic, and other non-porous surfaces.
When applied to stainless steel or other metals, it can cause staining and corrosion of the metal.
Additionally, plumbers’ putty may not adhere effectively to the metal surface and could easily leak or pull away from it.
If you’re looking for a sealant for stainless steel, you should use an appropriate silicone sealant instead.