Dissimilar metals can be joined using the arc welding process if the proper filler metal is used.

• A. True
• B. False
• C. Often
• D. Sometimes

Answer: (B)

Dissimilar-metal welding with arc processes is not automatically reliable; filler metals can help but do not guarantee a sound joint. The main challenge is that different base metals have distinct alloying elements, melting temperatures, thermal expansion rates, and electrochemical properties. While selecting a compatible filler metal can adjust the weld chemistry and improve bonding in some cases, many dissimilar metal pairs form brittle intermetallic compounds, experience improper dilution, or suffer galvanic corrosion and high residual stresses. Because of these metallurgical constraints, you can’t say dissimilar metals can always be joined with arc welding simply by choosing the right filler—it's feasible only for certain combinations and conditions, not universally guaranteed.