Abstract: A method of applying a surface layer across a surface layer or joint between cladding layers on a clad metal plate or plates comprises forming a shallow chamfer along each opposing cladding layer edge and positioning over the said chamfers a corrosion resistant metal flyer-plate having a shallow generally V-shaped configuration, optionally applying a buffer layer of transmitting medium placed on the outside surface of the flyer-plate, further superimposing an explosive layer upon the cladding and buffer layers and detonating the explosive layer so as to weld the flyer-plate material at least to the cladding layers. Advantageously a metal groove may be formed in the base metal layer of the clad plate to facilitate positioning of the flyer-plate, the groove wall conveniently being extensions of the cladding chamfer surfaces.