What Are Cylinder Blocks Made of？

1. Cylinder block

The cylinder block is the most basic component of the engine, and various components are directly or indirectly installed on it.

The material of the cylinder block is divided into two types. One is cast iron, which is generally cast with gray cast iron. In order to enhance the strength and wear resistance of the cylinder block, the current engine also uses high-quality gray iron containing nickel, chromium, molybdenum, phosphorus, and other elements. And some high-strength diesel engines will be cast with more advanced ductile iron or vermicular graphite iron. The strength, rigidity, wear resistance, and ability to absorb the vibration of the cast iron cylinder block are all excellent, but the biggest disadvantage is its heavy weight.

For the gasoline engines used in small cars now, more cylinder block for sale is aluminum alloy, or aluminum-magnesium alloy cylinder block. They are made of aluminum alloy or aluminum-magnesium alloy. The biggest advantages are light weight and good heat dissipation, but the strength, rigidity, wear resistance and vibration absorption ability of the cylinder block are not as good as cast iron cylinder blocks. Therefore, those Internet trolls who brag about the superiority of aluminum alloy engines all day long can stop.

2. Cylinder head

The working conditions and structural complexity of the cylinder head and the cylinder block have many similarities, so the two are generally cast with the same material, which is also gray cast iron or alloy cast iron. Some gasoline engines use aluminum alloys to cast cylinder heads in order to improve heat dissipation and reduce engine weight. However, aluminum alloy has low strength and is easy to deform during use, so it can only be applied to gasoline engines. Diesel engines are still cast with higher-strength cast iron.

3. Cylinder liner

The cylinder liner is inlaid on the cylinder block, and the piston and piston ring moves up and down in it, so it must be very wear-resistant. Therefore, it is generally made of high-grade cast iron with good wear resistance, such as pearlitic cast iron, alloy cast iron, high phosphorus cast iron, boron-containing cast iron, etc. It should be noted that whether it is a cast iron engine or an aluminum alloy engine, the cylinder liner is cast iron, and the aluminum alloy engine must also be inlaid with a cast iron cylinder liner. Now there is a more advanced technology, which is to directly use metal spraying technology on the aluminum alloy cylinder block, spray a layer of dense and wear-resistant iron coating, and then use laser quenching to enhance hardness and wear resistance, which can greatly reduce Engine weight and volume. However, such an engine cannot be repaired. If there is a cylinder explosion failure, the engine can only be replaced directly.