Cu-Ni castings and wrought pipes nominally contain 1% Fe to 2% Fe, which is added to improve the Cu-Ni alloy's erosioncorrosion resistance. After fabrication, Cu-Ni products are solution heat-treated to dissolve the iron uniformly andform a single-phase alloy. During welding, however, iron can precipitatefrom solid solution onto grain boundaries in the heat-alfected zones (HAZ). During seawater...