Influence of dry friction on subsurface structure of sintered composite Al—7Sn—38Fe

The subsurface macrostructure of a sintered Al—7Fe—38Sn composite, which is formed upon rotation of a flat steel bar pressed to it, has been studied. It was established that a zone of intense plastic flow is formed under the friction surface of the composite due to thermal softening. The size of the zone increases and the refinement degree of the structural elements in it increases as the applied pressure and sliding speed increase. The thickness of the plastic flow zone is ∼200 µm at a pressure of 15 MPa and increases with increasing pressure. A thin layer with a homogeneous ultrafine crystalline structure is formed between the friction surface and the plastic flow zone.