Steel may seem like an unsuitable material to cylinder sleeves manufacturers for making cylinder liners. The density of the steel is almost three times of aluminium. The thermal expansion of the steel is much lower than the aluminium piston that runs inside it, and it also has low thermal conductivity.
Still there are manufacturers that use the steel for making liners and you can expect the lowest total engine mass, despite its density. The major benefit of using steel for constructing cylinder sleeves is its strength and stiffness.
Cylinder liners made of aluminum are popular products as they conduct heat well. As compared to steels, the allowable stresses in aluminium are low, which increases the thickness of material to maintain stress within allowable limits. This implies the water jacket and the material surrounding it are bigger.
Problems with aluminium:
The usual effects are that the engine block is heavier, and the crankshaft is heavier and longer. Another one is that the cylinder head fasteners are forced by the combustion chamber, which increases bending stresses.
Even if the aluminium cylinder liners are usually lighter when compared to their steel counterparts, the new design of engine with aluminium liners is heavier.
Aluminium based liners can also get damaged by cavitation, hence manufacturers put coating on the exterior of the liner surface to make it more resistant to cavitation. However, when it is steel liners, cavitation doesn’t happen, still the products need surface treatment to prevent excessive corrosion.
The thermal conductivity is not so bad as well. Steel cylinder liner can be thinner as compared to aluminium to match fatigue stresses or displacement. This implies that the rate of heat transfer can be high for steel component as for an aluminium one.
There is nothing to tell about the steel strength that can help offset the fact that the thermal expansion coefficient is lower than the aluminium. Manufacturers need to understand that they should use larger cold clearance between the piston and liner to match the thermal expansion coefficient of aluminium.
Though the steel is not designed for use as a cylinder liner material, still manufacturers apply it for cylinder liners. The material is not widely available, nor is it easy to source in suitable liners sizes.
For more details on Cylinder Liners, you can write a mail to cylinder sleeves manufacturers, Cylinder Liners India. They are best suppliers and exporters of liners and sleeves products throughout the globe.