Compared to similar methods, SMC benefits from a very high volume production ability, excellent part reproducibility, it is cost effective as low labor requirements per production level is very good and industry scrap is reduced substantially. Weight reduction, due to lower dimensional requirements and because of the ability to consolidate many parts into one, is also advantageous. The level of flexibility also exceeds many counterpart processes.
Since the first moulding compounds based on UP in the 1930s and the industrial startup in the 1950s this class of materials has developped into a variety of high performance polymers for various fields of application with a broad range of tailor made performances.
Thermal resistance
All thermoset polymers are known for their excellent thermal resistance. Using specific resin systems thermal resistances up to 300°C can be achieved. From technical view these materials are superior to engineering thermoplastics and especially the more economic alternative solution in comparison to high performance thermoplastics.
The combination of crosslinked polymer and high inorganic filler content by maintaining the excellent moulding characteristics make SMC and BMC materials the first choice for applications where elevated service temperatures are required or high temperatures can occure temporaryly.
For demanding engineering applications it is also cruicial that the CoTE is close to metals and ensure excellent performances in all tempreatures.
Fire retardancy
High fire retardancy isowadays most important for many applications and markets. To achieve high flame retardancy a number of additives can be used for different polymers. SMC and BMC do not contain any halogenes or other hazardous flame retardants. Still they can be formulated having excellent properties even at very low wall thicknesses.
Precision
SMC and BMC are first choice solutions for substitution of high performance metal parts where high precision is achieved through post machining. Tightest tolerances can be produced directly without post operations and ensure not only cost savings but also increased profitability.
As a main advantage towards competing non thermoset polymers, the possible compensation of shirinkage make even most challenging jobs feasable. For highest precision materials with negative shrinkage (expansion) will be used.
Weight reduction
In times where fossil fuels are running out at the same time as the environmental stress must be reduced, high performance composites can contribute with components with less weight and lower energy consumption. The mechanical properties of SMC and BMC make the substitution of a wide range of metal parts not only feasable but also quite easy.
Electrical performance
Excellent electrical performances have from the beginning of the plastics era been one of the biggest advantages of thermoset materials. Additionally to the excellent electrical properties of thermosets SMC and BMC show even higher performances especially in the parameters of electrical strength, water absorption and surface resisitivity.
Contrary to the excellent isolation properties also materials with reduced surface resistivity and elevated conductivity are available.
SMC and BMC cover the full range of electrical requirements, isolating and conductive.
Class A surfaces
Excellent surfaces for online- and offline painting as well als metallizing are a domain of especially SMC but also BMC parts. The surface results from the unique technology to comensate the material shrinkage.
Low emissions
Interior parts not only in the automotive industry require low emission materials. Any hazardous or unconfortable emissions and smell are restricted.
Also the lighting system's headlamp reflectors must be free of any emissions to avoid the feared fogging which reduces the lamp's performance.
Conclusion
Naming only some of the characteristics of SMC and BMC it already prooves the unique positioning as a high performance - highly profitable material class with enormous potential for the future.
The ability of SMC and BMC to tailor sew performances to specific application demands will expand the usage of these materials significant in the future.
