SMC BMCVersatility and high performance
SMC and BMC
SMC and BMC are broadly used in a wide range of applications and end-use markets, as they allow cost-effective manufacturing of highly complex parts in medium to high production series. These versatile material systems combine high mechanical strength, shaping flexibility, electrical or thermal insulation, and superior surface aesthetics. The combination of these would not be possible to realize in metal parts at acceptable cost.
High strength and stiffness
The combination of fibers, fillers and resins results in material systems with great stiffness and high mechanical strength. The resin provides the ductility, durability and system cohesion. The fibers are largely contributing to strength and stiffness.
Weight reduction
SMC BMC components can be designed to take similar loads as steel and aluminium at much lower weight, particularly in multi-axial bending situations (e.g. truck body parts). This results in a reduction of Eco-footprint, lower fuel and power consumption in transportation applications, and easy installation in building and construction. The high mechanical properties and manufacturing robustness of SMC BMC components help to replace a large number of metal parts into a single composite part.
Precision and predictability of dimensions
SMC and BMC are first choice solutions for substitution of high performance metal parts where high precision is obtained only by means of post-machining processes. With SMC and BMC, tight tolerances can be produced directly without post operations, ensuring not only cost savings but also increased process output and profitability.
The ability to compensate inherent resin shrinkage with special additives is an important advantage of SMC and BMC compared to equivalent thermoplastic materials. This allows engineers to create unique part designs with high mechanical strength and superior surface quality.
Resisting elevated temperatures
SMC and BMC are known for their excellent thermal resistance. Depending on the specific resin system used, heat resistances up to 300°C can be achieved. From a technical view these materials can be superior to conventional engineering thermoplastics, and provide cost effective solutions especially in comparison to high performance thermoplastics.
For demanding engineering applications it is crucial that the CLTE (Coefficient of Linear Thermal Expansion) is close to the CLTE of metals and ensures dimensional stability over a wide range of temperatures. The CLTE of SMC components (12-16 x 10-6/°C), is very similar to the CLTE of steel (12 x 10-6/°C) and aluminium (24 x 10-6/°C).
Part safety through great fire retardancy
Elevated resistance to fire and low smoke generation is important for many applications and markets, including public transportation, electrical vehicles and electrical switchgear.
SMC and BMC do not contain any halogens or other hazardous flame retardants. Still they can be formulated having excellent flame retardant properties, even at very low wall thicknesses.
Electrical performance
Typically, SMC and BMC feature excellent electrical properties, particularly dielectric strength, water absorption and surface resistivity. Despite of their excellent electrical insulation properties, also materials with reduced surface resistivity and elevated conductivity are available.
Great Class A surfaces
The ability to obtain excellent surface aesthetics is an important benefit of SMC and BMC. Parts can mass-colored, painted (both online- and offline), as well as metallized. These great surface aesthetics can be obtained through the unique low profile technology used in SMC BMC formulations, allowing to compensate the material shrinkage during cure.
Low emissions
Interior parts in many end use markets require low emission materials (e.g. when used in car or train interior parts). Minimization of hazardous or uncomfortable emissions and smell is highly desired, which is possible to obtain with SMC and BMC. In lighting systems the headlamp reflectors must be free of any emissions for avoiding lens fogging and reduction of lighting performance.
