This piston for internal combustion engines, which is capable of achieving high heat shielding properties and high durability, comprises: a base that is formed from aluminum or an aluminum alloy; a composite material part which is formed in a first region of the surface of the base, and which is formed from a composite material that is reinforced with inorganic fibers or whiskers; and an alumite coating film that is formed on the composite material part and a second region of the surface of the base, said second region being different from the first region.

A piston includes an upper member having a crown and a combustion surface extending radially inward from the crown. The upper member includes concentrically oriented first and second upper connecting surfaces integrally formed on the bottom side of the upper member. At least one of the upper connecting surfaces includes a curvilinear and/or multi-arcuate cross-sectional profile. The piston also includes a lower member having a pair of opposing skirts, each skirt defining a bore. The lower member also includes concentrically oriented first and second lower connecting surfaces integrally formed on a top side of the lower member. The lower member is integrally connected to the upper member by friction welding. The curvilinear and/or multi-arcuate profile enables a shortened distance between the top surface of the crown and the bore centerline of the bore. Methods of manufacturing the piston are also disclosed.

An internal combustion engine piston includes a crown surface including a low thermal conductivity part lower in thermal conductivity than a base material. The low thermal conductivity part includes a porous member made of a glass material lower in thermal conductivity than the base material, and impregnated with the base material. A first material is interposed at least partly between the porous member and the base material in the low thermal conductivity part, wherein the first material is water-soluble, and has a higher melting point than the porous member.

A cylinder liner for an internal combustion engine may include an aluminum alloy material including a magnesium content of at least 0.3% by weight, a liner body having a circumferential face, and an adapter layer of silicon oxide disposed on the circumferential face. The adapter layer may include at least one of a potassium oxide content and a sodium oxide content of greater than or equal to 0% by weight.

A heavy duty piston for an internal combustion engine comprises a thermally conductive composition filling 10 to 90 vol. % of a sealed cooling gallery. The thermally conductive composition includes bismuth and/or tin. For example, the thermally conductive composition can be a single-phase binary mixture of bismuth and tin. The thermally conductive composition has improved thermal properties, for example a melting point around 139 C., a thermal conductivity around 22 W/m.Math.K, and a thermal diffusivity around 1.43 E-5 m.sup.2/s. The thermally conductive composition is not reactive and does not include toxic or cost-prohibitive metals. During high temperature operation, as the piston reciprocates in the cylinder bore, the thermally conductive composition flows throughout the cooling gallery to dissipate heat away from the upper crown and thus improve efficiency of the engine.

A method for producing a cast component may include providing an insert part including an insert body having a circumferential face; coating the circumferential face with an adapter layer made of silicon oxide; arranging the insert part in a casting mold; and positively locking a casting encapsulation of the insert part and the adapter layer with an aluminum alloy to produce the cast component, wherein the aluminum alloy has a magnesium proportion of at least 0.3% by weight.

A method for producing a piston with a combustion bowl may include fastening an annular fibrous preform for reinforcing a periphery of the combustion bowl in a casting mold for the piston coaxially with a piston axis in a plane of a piston head. The method may also include introducing a metal melt into the casting mold to produce a piston blank, generating a pressure difference between the metal melt and the fibrous preform for infiltration of the metal melt into the fibrous preform, and machining the piston blank. The fibrous preform may be held in the casting mold by suction tubes in which a negative pressure may prevail such that the metal melt may be sucked into and infiltrate the fibrous preform. At least one section of at least one of the suction tubes may accelerate solidification of the metal melt passing into the suction tube.