
The comparison between ceramic cylinder liner and bimetallic cylinder liner mainly includes the following aspects:
1、 Material characteristics
Ceramic cylinder liner:
Ceramic materials have high heat resistance and wear resistance, and can withstand the erosion and friction of high-temperature gas. Generally, the heat resistance temperature of ceramic cylinder liners can reach over 1200 ℃.
Ceramics have high hardness and lower friction coefficient compared to traditional metal materials. They can effectively reduce the frictional resistance between the piston and cylinder liner, reduce the frictional work loss of the engine, and improve the efficiency of the engine.
Bimetallic cylinder liner:
Composed of two different metal materials, typically an inner layer of wear-resistant alloy and an outer layer of ordinary steel shell. This combination not only utilizes the wear resistance of the inner alloy, but also retains the strength and toughness of the outer steel shell, making the cylinder liner have both good wear resistance and certain mechanical strength.
2、 Thermal expansion performance
Ceramic cylinder liner:
The thermal expansion coefficient of ceramics is relatively small, and the size change is relatively small when the engine operating temperature changes. It can maintain good fit clearance stability, avoid the problem of excessive or insufficient clearance between the cylinder liner and piston caused by thermal expansion, and is conducive to the normal operation of the engine and the sealing effect of the piston ring.
Bimetallic cylinder liner:
Due to the combination of two different metals, there is a difference in the coefficient of thermal expansion. The thermal expansion coefficient of the outer steel shell is generally larger, while the thermal expansion coefficient of the inner alloy is smaller. During the operation of the engine, uneven stress distribution between the inner and outer layers may occur due to temperature changes, and long-term use may lead to potential faults such as delamination.
3、 Manufacturing cost
Ceramic cylinder liner:
The manufacturing process of ceramic cylinder liners is relatively complex, requiring special ceramic molding techniques and high-temperature sintering processes. The equipment and technical requirements are high, which leads to high production costs for ceramic cylinder liners.
Bimetallic cylinder liner:
The manufacturing process of bimetallic cylinder liners is relatively mature, mainly by combining different metal materials together through welding or composite casting, with relatively low production costs, making it easy for large-scale production and promotion.