Resin Transfer Molding (RTM)

Resin transfer moulding is a composite manufacturing method that combines injection molding with the use of reinforcing fiber material. The Resin Transfer Molding process is mostly used to manufacture complex composite parts with high durability. However, RTM has different types such as Light RTM, High-Pressure RTM, etc. Each type has its own advantages such as superior mechanical properties, fast production, or easy setup.

Due to its versatility, resin transfer moulding is used for manufacturing wide range of products such as airplane parts, missile and missile launchers, helmets, phone poles, panels, radomes, automotive parts, wind turbine wings, boat parts, bicycle parts. With an increased demand for carbon composite materials, it is expected that the resin transfer moulding will have a bigger impact in composite manufacturing.

RTM Process

Resin Transfer Moulding (RTM) is similar to injection moulding. The main difference is the use of reinforcing fibers. First, the molds are coated with a mold release. Then, the fibers are laid in between the male and the female moulds. The mold is closed and the resin is injected from an inlet port. Then, the composite is cured by heat. This could be achieved by either a curing oven or embedded mold heaters. After the curing process is competed, the part is moved to post processing.

High-Pressure RTM

High-Pressure Resin Transfer Molding (HP-RTM), is a type of RTM. Compared to conventional resin transfer moulding, HP-RTM, the resin is injected at significantly higher pressures up to 150 bars. Because of its higher complexity, the initial cost for HP-RTM is higher. However, the cycle time is significantly reduced compared to RTM.  Moreover, HP-RTM reduces void formation, so HP-RTM parts have better mechanical properties.

ADENTE uses a proprietary HP-RTM machine which allows pressures up to 100 bars. In addition, with a skilled engineering team, ADENTE is capable of developing and manufacturing the best HP-RTM parts for any project.

CostLow initial costHigh initial cost, lower cost per unit
Cycle TimesRelatively fast cycle timesExceptionally fast cycle times
Number of VoidsFew voidsFewer voids
Volume RatioHigh fiber volume ratioHigher fiber volume ratio
Part ComplexityProduction of complex composite partsProduction of complex composite parts
Overall WeightLow weightLow weight
Mechanical PropertiesSuperior mechanical propertiesSuperior mechanical properties

Some of our parts are manufactured with High-Pressure RTM, you can also visit the Products page for more information