Cylinder liners are made of different materials than engine blocks to better withstand heat and wear over time. Liners are composed of alloys that increase resistance to corrosion and abrasion while reducing thermal stresses. Common materials used in liners include cast iron for its strength and porosity, manganese and chromium for hardness and durability, and silicon to prevent the formation of white cast iron. The specific concentrations of these alloys in a liner determine its quality.

1. Materials Used to Make Cylinder Liners
Cylinder liners are important components of engine blocks as they minimize the damage incurred by it
over a period of time. In addition, they facilitate two of its most important functions i.e. conduction of
heat (to the coolant) and the even distribution of produced energy throughout the engine circuit. For
acquiring these traits, cylinder liners are composed of a mixture of elements that are unique to itself
and completely different from the ones used in cylinder blocks or jackets. However, that’s not all.
Cylinder liner exporters also highlight other reasons for such a difference in the chemical combination
of cylinder liners and jackets. Some of these can be enumerated as follows:
1. Increased Resistance to Physiochemical Degrading Agents
Liners reduce the intensity of corrosion, abrasive wear, and frictional force by taking up its effects on
itself. Hence, unlike cylinder jackets, liners are needed to have a longer resistance towards all the
degrading agents to ensure efficient internal mechanism in the engine block for long times.
2. Active Life Differences
While liners can be replaced with time and even renovated with newer engineering technologies,
cylinder jackets cannot be changed frequently or developed for producing much difference. Hence,
cylinder jackets are made of elements that have high tensile strength, ductility, and life, but liner
elements are carefully chosen to increase its physiochemical capabilities.
3. Preventing Undue Thermal Stresses
During operation, the temperature of a liner and the cylinder jacket are different, with the former being
hotter than the other. If the jacket and the liner of a cylinder are carved out of the same elements,
their expansion during temperature rises can cause uncontrollable thermal stresses in the block,
thereby making way for fractures or breakages in the engine components.
To achieve the functions mentioned above, a diverse range of elements is used in the making of
liners. Cylinder liner exporters often hand out an instruction book that contains all the list of ferrous
and non-ferrous elements that have gone in the making of their cylinder liner. So, here is a list of some
of the elements that are commonly used by nearly all liner manufacturers:

2. 1. Cast Iron
Even though it is the most basic and primitive form of iron (ductile iron being a more popular choice)
the use of cast iron in cylinder liner productions is immensely important. It is the singular element that
is as high in terms of its physical strength as its porousness. This allows manufacturers to efficiently
shape liners to any size while ensuring that the final product does not lose its ability to decrease piston
seizures and extensive galling.
2. Manganese
It is a rare element that is used to coat the inner surfaces of the liner. Its basic function involves
increasing the mechanical properties (ductility, tensile strength, etc.) of the liners.
3. Chromium
It is used in minute amount for providing textural hardness to the final product supplied by cylinder
liner exporters. In addition, it also improves the endurance of the liner to corrosive agents.
4. Silicon
This non-ferrous element is an unlikely component of liner that prevents the formation of white cast
iron, as a result of chemical processes, in the block. Rather, it increases the production of the desired
grey cast iron.
There are a number of cylinder liner exporters is the market today. And one must be careful while
purchasing cylinder liners from any of the available sellers because the quality of the product offered
by each may vary incredibly. While the liner elements remain the same, their concentration in its
mixture determines its quality. Hence, one should keep considerable knowledge about the engine
components handy for himself/herself while going for purchasing cylinder liner.
Source: Materials Used to Make Cylinder Liners