Automotive Applications using Molded Thermosets

Why are thermoset composites like phenolic and bulk molding compound commonly used material in automotive applications? Molded thermoset parts and components have excellent material properties with regards to resistance against high temperatures, corrosion, and chemicals and automotive fluids. Processing wise, thermosets may be injection molded, or compression molded. Thermoset injection molding is a fast-cycle process that can produce high volumes of parts with complex geometries that may be difficult or costly to achieve in metal or stainless steel. Property-wise, thermosets offer chemical resistance against many types of automotive fluids such as oils, transmission fluids, and coolants. Whereas a thermoplastic molded part may degrade in such chemicals and oils, thermoset parts remain durable and strong, allowing an internal product assembly to remain safe for use. Another material benefit of thermoset composites towards automotive applications is thermosets heat resistance and ability to withstand high operating temperatures.

Applications near an engine or transmission may see elevated operating temperatures, requiring a part to withstand such temperatures and heat without disforming or creating safety hazards in the application. Another emerging industry for thermosets is the electrification efforts in the automotive industry with Electric Vehicle (EV) components. Thermosets offer excellent arc and track resistance along with very strong dielectric and electrical insulation performance, making thermosets suitable for electrical covers, housings, power and terminal blocks, battery components, and other applications that experience electrical voltage or wiring. Cost-wise, thermoset composites such as Bulk Molding Compounds (BMCs) and Phenolics are priced competitively in the $1.00 – $3.50 range depending on commercial volume and formulation, allowing them to compete with advanced thermoplastics and metallic solutions at an advantageous price point for raw material.