SMC (SMC Composition)
SMC is a type of fiber reinforced composite material which primarily consists of a thermosetting resin, glass fiber reinforcement and filler. Additional ingredients such as low-profile components cure initiators, thickeners, process additives and mould release agents are used to enhance the performance or processing of the material

As with any material system, be it metallic or plastic, SMC can be formulated to meet specific performance requirements of a particular applications, such as tensile loading or class "A" surface.

In addition to the number of different materials that can be combined, there are also different forms and proportions of each material. Glass fibers in SMC are chopped into lengths of 12 mm to 50 mm. The amount can vary from 25% to 60% by weight. Trade -off is usually performance and process ability vs. cost.

RESIN TRANSFER MOULDING
RESIN transfer moulding (RTM) is as closed mould semi-mechanized manufacturing method for making fiber reinforced thermoset plastic product. In this method, the reinforcement fiber is packed in the required geometrical arrangement in the cavity of a closed mould and a liquid resin of low viscosity is injected under pressure into the cavity. The resin wets the reinforcement and is then cured. Since fast curing polyester or epoxy resins are used, the RTM process gives faster production cycles than hand lay-up method gives.

RTM is a manufacturing process for FRP is known for more than four decades, but it is the development of resin injection machines and special reinforcement fiber mats and reforms that has helped the raid progress of this has helped the rapid progress of this method in recent years.