What material is the engine cylinder made of?

[DiGriffin]

The cylinder block of an engine is made of materials such as cast iron, alloy cast iron, and aluminum alloy. Advantages of alloy cast iron: Alloy cast iron has sufficient strength, good casting and cutting properties, as well as excellent wear resistance, high vibration damping, low notch sensitivity, and superior machinability. Advantages of aluminum alloy: Aluminum alloy cylinder blocks are becoming increasingly common because they are lightweight, have good thermal conductivity, and allow for a reduction in coolant capacity. After startup, the cylinder block quickly reaches operating temperature, and since it has the same thermal expansion coefficient as aluminum pistons, the change in clearance due to heat is minimal, reducing impact noise and oil consumption. Additionally, having the same thermal expansion as aluminum alloy cylinder heads reduces thermal stress caused by thermal shocks during operation.