Rev up car engine performance with silicone

Find a car without silicone and that is the day when pigs fly. An unlikely feat indeed which goes to show that silicone is essential to the car manufacturing process, especially when it comes to building engines. Let’s take a closer look at how silicone can rev up engine performance.

The engine is a critical component of a car’s powertrain system as it transforms energy to propel the car forward. This is a huge challenge, thus an engine could not fulfill its function without silicone. Contrary to popular belief, silicone is not only for manufacturing goods but can also be used to ensure optimal engine performance thanks to its three pillars of strength: durability, adhesion and elasticity.

Silicone in gaskets and hoses and seals, oh my![1]

Strolling through the deepest corners of a car engine, you would see that silicone is present in many components, mainly gaskets, hoses and seals. In each of these, the role of silicone is to improve the interactions between the parts and ultimately optimize engine performance.

  1. Head gaskets form the critical seal between the cylinder head and the engine block to close off the cylinders and create the combustion chamber. They must be able to ensure maximum compression under extreme temperatures and prevent engine gases and fluids from leaking. Silicone applied to the head gasket tightly seals off seams and prevents serious engine damage due to leaks. The result is long-lasting seals and gaskets and in turn a healthy, happy engine.
  2. Multi-layer steel gaskets are composed of different layers of steel sandwiched together. Silicone is used as a coating for these types of gaskets to prevent them from sticking to other metallic parts in the engine and to improve cold sealing. Silicone has anti-stick properties but also great adhesion properties, depending on formulation. In addition, thanks to its elasticity, silicone easily adapts to varying coefficients of thermal expansion which is especially useful on multi-material seams. Example of this would be steel, aluminum and plastic.
  3. Formed-in-place gaskets tend to have very complex designs and so liquid silicone is used to form gaskets directly in an enclosure. This ensures tightness and cohesion between intricate parts.
  4. Turbo hoses connect the air cooling system, engine and piping. As they are in extreme proximity with the engine, they are made of silicone to enable them to withstand high temperatures.


Extreme conditions call for extreme protection and durability

Things can really heat up in a car engine. Since it is a high voltage circuit that requires a spark to start, sensors and electronic components are at risk of being damaged. Polyurethanes and epoxy are frequently used to provide thermal protection; however, they only work up to a certain degree. Temperatures inside an engine can peak at 150ºC; therefore, your best bet for standing up to such extreme conditions, up to 300°C is silicone. It resists high temperatures and has dielectric properties, and is thus perfect for providing insulation. Sensors and electronic components are encapsulated in silicone in a process known as potting to protect them from sparks and thus ensure their integrity over time.

As an added plus, silicone having a much higher temperature yield means that the temperatures of an engine can be increased,supporting a world wide trend: making cars more fuel-efficient.

Lastly, silicone is very durable thanks to its chemical stability and also stands up well to the test of time. It defends itself against aging and stress while resisting corrosion from chemical agents such as engine lubricants and battery acids.

Durability, adhesion and elasticity are the three pillars of strength that make silicone an essential part of any car engine.

For further information, please feel free to contact a Elkem Silicones representative who will be happy to assist you.

[1] Intertextual reference to the famous line in the film Wizard of Oz… « lions and tigers and bears, oh my! »