Abstract: The invention relates to lids of easy-opening cans for perishable foodstuffs, and a method of obtaining them. These lids are composed of a metal foil and a plastics film, the metal foil having a mechanical non-traversing pre-incision corresponding to a tearing line and the thermo-shrinkable plastics film having a continuous depression situated opposite the mechanical pre-incision. The pre-incision and the depression, obtained by the action of heat, makes it possible to avoid the defects known as "feathering" and the plastics film is less expensive and more resistant to corrosion than is conventional lacquer.

Abstract: Castings made from aluminum and its alloys have at least one face including at least one region of wear-resistant zones. These castings are formed by a controlled distribution of zones hardened by local melting effect. The zones, no matter what their length and shape, have a width and depth between 3 and 150 .mu.m and the surface fraction or percentage of the zones for the wear-resistant region is between 5 and 60%.