Abstract: This invention relates to internal combustion engine liners having a base of aluminum-silicon alloys and of silicon grains and processes for obtaining them.It is characterized in that these grains are carefully graded in size and dispersed in the alloy matrix. These liners can also contain at least an intermetallic compound such as Ni.sub.3 Sn, for example.These liners are obtained by extrusion or sintering of a mixture of powders.The invention has its application particularly in the automobile industry and in any type of industry where it is desired to have liner-piston units from aluminum alloys having a good compatability.

Abstract: This invention relates to inserts for pistons of diesel engines of aluminum-silicon alloys obtained by powder metallurgy.These inserts are characterized in that they contain elements such as iron and zirconium.They find their application in the manufacture of pistons intended to work at high temperatures for long periods and exhibit a good friction capacity.

Abstract: The invention relates to cylinder liners for internal combustion engines comprising a matrix based on aluminum alloys of high mechanical strength, obtained by powder metallurgy, and methods of producing them. The liners comprise a dispersion of grains of an added intermetallic compound, apart from the dispersion of such intermetallic compounds as may exist in the alloy, the added compound having a melting temperature of over 700.degree. C. The liners are obtained by extruding or sintering a mixture of powders. The liners of the invention may be used particularly in the automobile industry and in any kind of industry where liner-piston units of good compatibility must be obtained from aluminum alloys.