Today,SMC used worldwide and represent a major part of the world's thermoset composites.Globally,the compression molding of SMC is the third most intensively used technique for the production of polymer composite parts worldwide(behind the injection of reinforced thermoplatics and the hand lay-up techniques).It represents about 15% of the total of produced parts and of the total of materials used by the composite industry.
There is a large diversity of fields of applications for SMC.The automotive and truck inductries remain the drivers of the SMC technology,but SMC are commonly used in the agricultural ,rail and marine(interior and body parts,watercraft parts,etc),electrical(low voltage and mdeium voltage energy systems,fuses and switchgear,cabinets and junction boxes,encapsulation of wirings and electronic circuits,electrical components with reduced surface resistivity,lamp housings) and energy(parts for wind turbine ciruits,electrical components with reduced surface resistivity, lamp housings) and energy (parts for wind tur-bine and solar power applications, etc.), sanitary (sinks and bath tubs, toilet seats, drain covers, etc.), domestic appliance (blower housings, drain pans, and heating, ven-tilation, and air conditioning (HVAC) systems, vent trims,parabolic mirrors, swimming pool panels, etc.), building and construction (drinking water tanks, panels, doors,etc.), and medical (surgery equipment, dental medication systems, antibacterial components) sectors.
In the automotive and truck industries, SMC parts are used notably in exterior and interior body panels,painted (class A parts) and unpainted, semistructural and structural parts (cf. Fig. 2). Basically, class A means that the surface finish has to exhibit an aspect of flatness,smoothness, and light reflection similar to that of stamped steels. A nonexhaustive list of automotive parts gives, for instance, bumpers, fenders, trunk divider, hood and door assemblies, deck lids, body panels, fenders, roof panels, spoilers, step assists, back panels, wheelhouses, firewalls,grilles, tailboards, cargo lids, stowage tubs, headlamp housings, and supports. More recently, high temperature underhood parts have been developed (e.g., valve covers).
SMC in aerospace are still rare. Nonetheless,allied with carbon fibers, SMC are penetrating the aeronautic indus-trial field for extra-wide-body commercial aircrafts (e.g.,large window frames, secondary structures, and interi-ors). Their performances are then between standard SMC and a quasi-isotropic laminate and meet the requirements of tight geometrical tolerances and weigh half as much as aluminum alloys. Finally, SMC are also spreading in sporting and leisure goods (bicycle components, etc.).
