An aluminum alloy for a piston may include aluminum (Al) as a base, magnesium (Mg) and zinc (Zn); and wherein the magnesium content is 10-20 wt % with reference to the total weight. In the aluminum alloy, the zinc content is 2.0-6.4 wt % with reference to the total weight. The aluminum alloy further includes copper (Cu) of 1.5-3.5 wt % with reference to the total weight. In the aluminum alloy, T-AlCuMgZn phase is generated.

A method for producing a piston blank or a piston for an internal combustion engine, includes providing a thickened portion formed in at least one box wall in the direction of thickness approximately in the center thereof, which is at least partly flush with a cooling channel. A resulting piston blank or piston having these features can be made in a casting mold or forging die designed in a corresponding manner.

A cast light metal piston for an internal combustion engine may include a piston crown and a piston skirt adjoining the piston crown. The piston skirt may include two skirt walls arranged on a pressure side and a counterpressure side, respectively. The piston skirt may have two box walls connecting the skirt walls, which conically taper towards one another in a direction of the piston crown. The piston may include an annularly encircling cooling channel. A thickness of the piston crown may amount to a maximum of 4.5 mm.

A method of manufacturing an engine piston may include performing upper-body formation for forming an upper body as an upper portion of a piston body by pressing a powder-type sintered material, performing lower-body formation for forming a lower body as a lower portion of the piston body by pressing a powder-type sintered material, performing bonding for forming the piston body by providing a brazing material between the upper body and the lower body and brazing the upper body and the lower body to each other while sintering a sintered material, performing machining for removing pores from the surface of the piston body by machining the surface, and performing heat treatment for forming a passive film by performing at least one of nitriding heat treatment or oxidation heat treatment on the surface of the piston body.

An improved piston forging for use in an internal combustion engine is disclosed. The piston forging comprises a crown, a pair of pin towers extending generally axially away from the crown, and a skirt extending generally axially away from the crown. The improved piston forging further comprises a plurality of grains flowing across the piston forging. The plurality of grains are reoriented during the forging operation into a configuration that follows the surfaces and features of the piston forging. More specifically, the plurality of grains are reoriented in a manner that is most beneficial to resist combustion and inertial forces that are enacted upon a machined piston during operation.

A piston and process for manufacturing a piston includes an upper part providing an upper combustion surface including a top land, a land ring and a combustion bowl. An undercrown surface is formed under the combustion bowl. A lower part including pin bosses and a piston skirt are formed under the undercrown surface. At least one of the upper part and the lower part are formed with metal injection molding.

A piston for an internal combustion engine and method of construction is provided. The piston has a robust, lightweight monolithic piston body including an upper wall forming a combustion bowl depending radially inwardly from an annular, uppermost combustion surface. An undercrown surface is formed on an underside of the combustion bowl, with at least a portion of the undercrown surface being bounded by diametrically opposite skirt portions, pin bosses and strut portions connecting the skirt portions to the pin bosses. The bounded undercrown surface has an openly exposed surface area, as viewed looking along a central longitudinal axis along which the piston reciprocates, providing an expansive area against which oil being splashed or sprayed can come into direct contact with to enhance cooling the piston while in use. Through channels extending over upper regions of the pin bosses can be provided to further reduce weight and facilitate cooling.

The present invention relates to a process for producing a piston made of hypereutectic AlSi alloy with a cast iron Alfin ring and a piston obtained through said process. The process according to the invention allows to obtain high adhesion of the Alfin ring to the piston body, making it particularly suitable for use in high performance engines.

A piston for an internal combustion engine includes: a pair of groove portions which are positioned on the back surface side of the crown portion, and which extend along outer wall surfaces of the apron portions, each of the skirt portions having a width in the circumferential direction of the piston, the width being gradually decreased toward a piston axially lower side which is an axial direction of the piston from the piston crown surface toward the back surface of the crown portion, and each of the groove portions being positioned on an outer side in a radial direction of the piston as the each of the groove portions is positioned on the piston axially lower side, an entire of the each of the groove portions being inclined with respect to a center axis of the piston.

Piston has crown portion 2 having crown surface 2a defining combustion chamber, thrust-side and anti-thrust-side skirt portions 3a, 3b formed integrally with crown portion and sliding on cylinder wall surface, a pair of apron portions 4a, 4a joined to skirt portions in circumferential direction, recessed portion 6 formed on back surface that is opposite side to crown surface and extending between skirt portions along substantially longitudinal direction, and a plurality of protrusions 7 formed integrally with bottom surface of recessed portion and extending along arrangement direction of skirt portions. At least one end edge in longitudinal direction of protrusion is integrally connected to inner side surface, facing one end edge of protrusion, of recessed portion. Adequate transcription performance to molding surface can therefore be ensured while removing remains of air on bottom side of recessed portion of mold for molding protrusions on crown portion back surface during casting.