Abstract: A layered composite construction material, especially for sliding and friction elements, with a substrate, for example a steel layer, on which is a copper-containing or a tin-containing intermediate layer and then a tin-containing or copper-containing functional layer, together with an interposed diffusion barrier layer. Diffusion of tin between the functional and intermediate layers is minimized by forming the diffusion barrier layer by cathode sputtering of a metallic material which has essentially a cubic face-centered crystal lattice that is built up under a recrystallization process. Vacancy sites in the crystal lattice structure are avoided or removed, and a space filling of from 60% to the optimum 68% is achieved. Preferably the diffusion barrier layer is a nickel-tin alloy having a tin content of at least 10% by weight.

Abstract: A composite structural material particularly intended for frictional and slide elements, consisting of a substrate such as a steel layer with a copper- or tin-containing intermediate layer, a tin- or copper-containing functional layer and, between these last two layers, a diffusion barrier layer protecting against diffusion of tin from the functional layer into the intermediate layer or back to the diffusion barrier layer. The diffusion barrier layer consists of a metallic material having a hexagonal crystal lattice, which material is applied by cathodic sputtering, forming a material structure that is densely packed in vacuo with a space filling by metal ions of above 70%. For the cathodic sputtering, conditions of plasma pressure and substrate temperature can be chosen so that recrystallization occurs simultaneously with the formation of the diffusion barrier layer; this makes it possible to achieve the densest hexagonal packing, with a space filling of up to 74%.