Foam and sponge are versatile materials that lend themselves to producing cut parts that satisfy a multitude of automotive applications. From suppressing squeaks and rattles, to air management seals and baffles, these parts are an important component in today’s fuel efficient and lightweight vehicles. In this blog we examine the foam and sponge cut parts for automotive applications that CRG can supply.

About foam and sponge materials

Foam and sponge are distinct materials that exhibit different mechanical and physical properties which support a wide range of uses and purposes.

Foam rubber is produced when a gas is blown into a liquid mixture, creating numerous small bubbles. Sponge, on the other hand, consists of two types: open cell and closed cell. Open cell sponge is formed in a mold. Sodium bicarbonate is added to the uncured rubber material in the mold. The sodium bicarbonate “effervesces” to create a network of open and interconnected cells. Closed cell sponge, in contrast, is formed when released nitrogen gas creates bubbles that remain completely closed within the material. Closed cell sponges have a more solid, yet lightweight structure, while open cell sponges are softer and more breathable.

A hybrid material is semi-open cell foam which is created by physically bursting the closed foam cells during the setting process to create an amalgam product which is softer and easier to compress.

Foam and sponge materials may be made from a variety of rubber compounds. EPDM, silicone, and microcellular urethane (Poron®) are some of the more common types of foams and sponges which CRG uses to service automotive applications.

 Foam and sponge materials: automotive applications

Because of their different properties and characteristics, foam and sponge materials will support a variety of applications. With their more solid structure, closed cell sponges are a preferred material to for the following applications:

Softer open cell sponges are usually preferred material for the following applications:

With a wide range of foam and sponge material formulations available in the marketplace today, choosing the right material is important for ensuring that the finished part will perform as intended in the target application. Criteria that should be considered when selecting a foam or sponge material for an application includes the following:

In serving the needs of our customers with foam and sponge cut parts for automotive applications, CRG has a proven capability. We work with each customer early in their project to assist with part design and material selection. Parts are developed to meet all quality standards using a production part approval process (PPAP), and all parts are produced using CNC cutting technologies under the guidance of experienced operators.

In the production phase of a project, CRG uses proven processes while adhering to recognized quality standards, such as ISO 9001:2015, to ensure reliable and consistent part quality. In every project, we maintain our commitment to 100 percent on-time delivery, whether utilizing demand-pull replenishment or JIT scheduling.

CRG supplies parts which meet ASTM D1056 line call-outs, as well as the material specifications of major OEM’s, including those of General Motors, Ford, Chrysler, Nissan, Mazda, BMW, Honda, Toyota, Volvo, and Mercedes-Benz. In those cases where a new specification is required, we work with our supply chain partners to develop an appropriate solution that meets or exceeds all requirements. To find out more about the foam and sponge cut parts which CRG can supply, please contact our sales department at


Electrical Applications

Rubber Grommets for Flexible Wiring and Cabling

Rubber grommets are widely used in industrial and automotive applications to protect wiring and cabling on installations that feature rough edges or...

Automotive & OEM

Gaskets, Seals and Parts for Electric and Autonomous Vehicles: Key Challenges

Today’s cars are more technologically advanced than ever Vehicles coming off the asembly line today have standard features that would have been...

Automotive & OEM

Rubber Parts and Materials: How to Read ASTM D2000 Specifications

A key challenge for buyers of rubber parts is how to specify and communicate the desired material requirements to a supplier Accurately communicating the...