Nickel-based alloys having improved localized corrosion resistance, improved stress-corrosion cracking (SCC) resistance and impact strength are disclosed. The improvements come from the provision of compositions that are resistant to deleterious phase formation and from the addition of alloying elements that improve corrosion resistance, impact strength, and SCC resistance. The nickel-based alloys of the present invention have controlled amounts of Ni, Cr, Fe, Mo, Co, Cu, Mn, C, N, Si, Ti, Nb, Al, and B. When subjected to post-cladding heat treatments or welding, the nickel-based alloys retain their corrosion resistance and possess desirable impact strengths.