Performance Requirements of Car Silicone for Turbocharged Systems

Supercharging is a technology that uses waste gas generated by internal combustion engines to drive air compressors. The main function of automotive turbocharging is to increase the engine's air intake, thereby improving the engine's power and torque, and making the car more powerful. However, after supercharging, the pressure and temperature of the engine during operation are greatly increased. Therefore, material improvement is also crucial when using turbocharging technology on engines. Aramid fibers can increase the strength of hoses, while silicone rubber can protect the fibers and make the finished hose flexible and resistant to ultra-high temperatures.

Car Silicone Rubber's High-Temperature Resistance

Gas produced during turbocharging is compressed and generates high temperatures due to severe friction. Even the gas that has been cooled generally reaches a temperature of more than 100°C. Therefore, the material of the hose used in the turbocharging system must be able to withstand a high temperature. Ordinary natural rubber, Butyl rubber, and styrene-butadiene rubber cannot meet the requirements of use under high-temperature conditions. Special high-temperature-resistant rubber materials must be used. As the pressure of turbocharging becomes higher and higher, the gas temperature passing through the pipeline also becomes higher and higher. If the pressure reaches 3.5×105Pa, the gas temperature passing through the pipeline can reach 250°C or higher, and the types of rubber that can be used in such a high-temperature environment are very few.

Car Silicone Rubber's Cold Resistance

Although the hoses are used in a high-temperature environment after the engine starts, the hoses are exposed to cold air after the car is parked. When the engine starts at low temperatures in cold areas in winter, the rubber hose vibrates at low temperatures. If the low-temperature resistance of auto silicone rubber is poor, the hose may tear, fall off, lose the shock absorption function, and other problems may occur due to becoming hard and brittle.

Automotive Silicone Rubber's Adhesion Strength

The rubber layer of the silicone rubber hose should maintain good adhesion with the reinforcing layer and the lining layer under harsh environments such as cold, heat, oil, and gas, and have a certain adhesion strength to ensure that delamination does not occur. Adhesion strength is related to the characteristics of the rubber itself and the rubber formula, as well as the impregnation and pretreatment of the reinforcing layer, the selection of adhesives, and the bonding process, which should be comprehensively considered.

Automotive Silicone Rubber's Processing Characteristics

Hardness and bonding strength of the liner can be considered, and these characteristics are closely related to their processing performance in rolling and/or co-extrusion processes.

In addition to conventional ordinary precipitated and gas-phase silicone rubbers, in order to meet more strict or special environments, various functional fillers must be added to develop personalized Auto Silicone Rubber, such as high-temperature resistance to 300 degrees Celsius, oil resistance, and flame retardancy, etc.