A practical concern related to an alloy’s susceptibility to inter-granular corrosion is the heat-affected zone of weldments. Welded test coupons of C-276 and C-22 alloys were exposed to an oxidizing sulfuric acid process solution.* C-276 alloy suffered unusually severe base metal, weld metal, and heat- affected zone attack in this particular environment. In fact only one-third of the coupon thickness in the heat-affected zone survived the corrosion test. C-276 alloy is seldom attacked to this degree in other media. There was minimal corrosion attack on the C-22 alloy sample.