Abstract: A weldment, such as the wall of a pressure vessel, is formed from segments, each of which includes a steel substrate, a protective layer of tantalum which is exposed to the interior of the vessel and an intervening layer of copper which lies between and is bonded to the substrate and the protective layer. The substrate and the two layers which form the cladding are explosively bonded together and the bonding procedure may leave the protective layer with small domes or embossments and pockets of trapped gas behind the embossments. The two segments are welded together edge-to-edge at their substrates, with their protective and intervening layers aligned. If one were to follow the traditional procedure, one would place a tantalum batten strip over the protective layers along the opposed edges so as to cover the edges, and then weld the batten strip to the protective layer along the edges of the strip.