Yes, IF the rules of proper splicing are followed, dissimilar metals can be successfully spliced.

Some of those rules that I can recall at the moment include:

• The part of the wires to be connected by splicing MUST be clean and free of any grease, dirt, corrosion, or deleterious material.
• A "sound" mechanical connection MUST be made. That means either the wires properly twisted together, OR a mechanical device [connector, wire nut, or some type of terminal used].
• If a twisted mechanical splice is used, then the splice joint should be soldered to both "lock" the twisted splice, and to prevent the atmosphere from getting into the wire interface, causing corrosion which will degrade the current carrying ability of the splice joint.