Foam injection molding

The main advantage of thermoplastic foam molding (TSG) is the reduction in density and thus material. This also has a positive effect on the environment and economy. Density reduction can be achieved by chemical or physical foaming. Chemical foaming as an established process can be realized quickly and easily by metering a chemical blowing agent. For this purpose, a standard injection molding machine is used with minor machine modifications. Physical foaming offers even greater lightweighting potential compared with chemical foaming. Here, the blowing fluid requires special machine technology. The Cellmould® unit of the Battenfeld HM-MK 180/525H/350V is available for this purpose in the technical center of the KUZ. This machine can produce lightweight components in both 1C and 2C operation.

Our services in 2K injection molding

  • Use our 2K injection molding machines Battenfeld HM-MK 180/750H/350V with Cellmould® unit and ENGEL Victory 330H 80V / 80 Combi for compatibility testing of your materials or also for sampling your 2K molds.
  • We support you in material selection and offer our extended material compatibility table as an aid
  • Examine the filling behavior of the material components meeting each other with our 2K cup.
  • Check adhesion and compatibility with the 2C tensile bar (link to molded parts catalog) or the 2C roller peel test specimen (link to molded parts catalog).
  • If you only have small quantities of material available, special 2C micro-molded parts and test specimens (link to molded parts catalog) are available in our micro injection molding department.

Use our possibilities for damping characterization by means of dynamic-mechanical-thermal analysis (link to magazine) with our new test rig!

Foam injection molding and sandwich effect combined

The sandwich effect causes the layers of a component furthest from the neutral axis to absorb the most bending forces. The closer the material layers are to the neutral axis, the lower the bending stresses and the lighter the foam can become in terms of lightweight construction. Ideally, the largest bubbles are located in the area of the neutral axis. In the direction of the edge layer, they become continuously smaller. Such a foam structure is called integral skin foam. Integral foam often forms during the chemical or physical foaming of thermoplastics: during injection, the melt solidifies immediately at the cavity wall, which impedes the formation of bubbles. The melt inside the component, on the other hand, cools only slowly, which promotes the formation of larger bubbles. A particularly rigid design using 2-component foam injection molding is possible with a combination of metal substitute plastic in the stiffness-relevant skin layer and a lightweight foam core, which acts as a shear-resistant spacer. The sandwich components can be mass-produced using a one-shot process and thus at low cost. The constructive application of the sandwich effect allows a lower weight for components that are mainly exposed to bending loads. As a special contribution to the circular economy and thus to sustainability, recycled material can be used in the core layer (2-component injection molding), as this is encapsulated by the compact, visually flawless skin material.

CT-Scan eines Sandwichbauteils mit chemisch oder physikalisch geschäumter Kernschicht

Our machine equipment at a glance

2 components injection molding machine

Battenfeld HM-MK 180/750H/350V


Additional equipment gas flushing unit



Additional equipment mold plate

2K sandwich intermediate plate

A & E Produktionstechnik GmbH

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Dr. Mathias Kliem

Lightweight construction / Sustainability