Rifeng E-Li

In-mold Foaming Cores
Lightweight design is a key requirement for many applications, and designers need to find innovative solutions, such as fiber reinforced sandwich structures. The design of these composite components can be complex, and the foam cores used for sandwich structures must meet many requirements while still maintaining cost and time efficiency.

Even geometries that were previously unable to be produced by CNC machining can now be produced quickly and easily by foaming in mold directly.

In this process, the polymethacrylimide (PMI) Pre-polymerization plate was crushed for particles, and through pre-foaming to get desired density, then these particles were put into a closed mold for heating, the foaming will start again, these particles will be constantly expanding, due to the mold cavity constraint, these particles will constantly to deform eventually fill the entire mold cavity, during the cooling phase, the polymer will turned stable, then can open the tooling and take out the shaped foam core as the mold cavity.

Rifeng E-Li offers the potential to lower cost per part through the reduction of waste, manual work and cycle times.

Processing and Production
Temperature resistance of up to 130 °C and pressure resistance of up to 3.5 MPa is achievable (depending upon density). Additionally, Rifeng E-Li is also suitable for most curing conditions used in the aerospace industry which require high compressive creep resistance at curing temperatures up to 180 °C and pressures up to 0.7 MPa. Rifeng E-Li is an ideal foam core for fast and efficient curing processes, not only for RTM or wet pressing, but also for high pressure RTM processes like compression-RTM.

Density Can Be Adjusted Upon Request
Depending on the mechanical properties required by applications or service conditions, core density can be adjusted during the foaming process to your choice of a core density between 75 kg/m³ and 150 kg/m³.

High Volume Production At Lower Per Unit Production Costs
Freedom of design – for complex geometries
Function integration – for integrated inserts, custom surface finishes, resin flow channels, etc.
Tailored and tight density range
High compression strength and temperature resistance at low density
Compatibility with fast curing processes
No hazardous ingredients

Mechanical Properties

• Compressive creep testing conditions

  Rifeng 75 E-Li 130℃ / 0.3MPa / 2h

  Rifeng 110 E-Li 150℃ / 0.3MPa / 2h

  Rifeng 150 E-Li 180℃ / 0.3MPa / 2h

• Technical data values presented are typical for nominal density, subject to normal manufacturing variations, not applicable for designing and acceptance. Please contact our QA team for material criterion and standard.

• Other density ranges are available upon request.