Cylinder liner comprising a supereutectic aluminum/silicon alloy for sealing into a crankcase of a reciprocating piston engine

A cylinder liner of a hypereutectic aluminum/silicon alloy,

• (A) said aluminum/silicon alloy being free of hard material particles independent of the alloy and consisting of, in percent by weight:
• Silicon 23.0 to 28.0%,
• Magnesium 0.80 to 2.0%,
• Copper 3.0 to 4.5%,
• Iron 1.0 to 1.4%,
• Nickel 1.0 to 5.0%,
• Manganese and zinc each at most 0.01%,
• the remainder being aluminum;
• (B) said cylinder liner containing primary silicon crystals and intermetallic phases having the following grain sizes, the numerical data denoting the mean grain diameter in μm:
• Primary Si crystals:
• 2 to 15 μm,
• Al2Cu phase:
• 0.1 to 5.0 μm,
• Mg2Si phases:
• 2.0 to 10.0 μm;
• (C) said cylinder liner having a precision-machined running surface, plateau faces of said primary silicon crystals and particles of intermetallic phases embedded in the running surface being exposed,
• wherein the cylinder is cast into a reciprocating engine.

A cylinder liner of a hypereutectic aluminum/silicon alloy,

• (A) said aluminum/silicon alloy being free of hard material particles independent of the alloy and consisting of, in percent by weight:
• Silicon 23.0 to 28.0%,
• Magnesium 0.80 to 2.0%,
• Copper 3.0 to 4.5%,
• Iron 1.0 to 1.4%,
• Nickel 1.0 to 5.0%,
• Manganese and zinc each at most 0.01%,
• the remainder being aluminum;
• (B) said cylinder liner containing primary silicon crystals and intermetallic phases having the following grain sizes, the numerical data denoting the mean grain diameter in μm:
• Primary Si crystals:
• 2 to 15 μm,
• Al2Cu phase:
• 0.1 to 5.0 μm,
• Mg2Si phases:
• 2.0 to 10.0 μm;
• (C) said cylinder liner having a precision-machined running surface, plateau faces of said primary silicon crystals and particles of intermetallic phases embedded in the running surface being exposed, wherein the depth (t) of at least one of the exposed plateau faces of the primary crystals relative to the surrounding alloy is about 0.3 to 1.2 μm,
• wherein the cylinder is cast into a reciprocating engine.

A cylinder liner of a hypereutectic aluminum/silicon alloy,

• (A) said aluminum/silicon alloy being free of hard material particles independent of the alloy and consisting of, in percent by weight:
• Silicon 23.0 to 28.0%,
• Magnesium 0.80 to 2.0%,
• Copper 3.0 to 4.5%,
• Iron 1.0 to 1.4%,
• Nickel 1.0 to 5.0%,
• Manganese and zinc each at most 0.01%,
• the remainder being aluminum;
• (B) said cylinder liner containing primary silicon crystals and intermetallic phases having the following grain sizes, the numerical data denoting the mean grain diameter in μm:
• Primary Si crystals:
• 2 to 15 μm,
• Al2Cu phase:
• 0.1 to 5.0 μm,
• Mg2Si phases:
• 2.0 to 10.0 μm;
• (C) said cylinder liner having a precision-machined running surface, plateau faces of said primary silicon crystals and particles of intermetallic phases embedded in the running surface being exposed,
• wherein, the running surface of the cylinder liner has a roughness with the following values:
• average peak-to-valley height Rz = 2.0 to 5.0 μm, maximum individual peak-to-valley height Rmax = 5 μm, core peak-to-valley height Rk = 0.5 to 2.5 μm, reduced peak height Rpk = 0.1 to 0.5 μm, and reduced groove depth Rvk = 0.3 to 0.8 μm,
• wherein the cylinder is cast into a reciprocating engine.