Composite epoxy material

From Wikipedia, the free encyclopedia

Composite epoxy materials (CEM) are a group of composite materials typically made from woven glass fabric surfaces and non-woven glass core combined with epoxy synthetic resin.[1][2] They are typically used in printed circuit boards.[3]

There are different types of CEMs:

  • CEM-1 is low-cost, flame-retardant, cellulose-paper-based laminate with only one layer of woven glass fabric.[4]
  • CEM-2 has cellulose paper core and woven glass fabric surface.
  • CEM-3 is very similar to the most commonly used PCB material, FR-4. Its color is white, and it is flame-retardant.[5]
  • CEM-4 quite similar as CEM-3 but not flame-retardant.
  • CEM-5 (also called CRM-5) has polyester woven glass core.[6]

See also[edit]


  1. ^ Inc, ANSYS. "Characterization of CEM-1 Boards". Retrieved 2022-01-20. {{cite web}}: |last= has generic name (help)
  2. ^ Andy (2023-05-02). "Composite Epoxy Material | What You Need to Know - FR Fabric". Retrieved 2023-07-20.
  3. ^ admin. "FR1-FR3, CEM1-CEM3,FR4, Aluminum Flex CCL introductions | PCB Blog". Retrieved 2022-01-20.
  4. ^ "Why Is Cem-1 PCB Material still Popular in the Circuit Board Market ?". Printed Circuit Board Manufacturing & PCB Assembly - RayMing. 2018-03-14. Retrieved 2022-01-20.
  5. ^ "CEM-1 PCB". Venture Elctronics. Retrieved 2022-01-20.
  6. ^ PCB Directory Editorial Team (12 July 2019). "What are Composite Epoxy Materials (CEMs)?". PCB Directory. Archived from the original on 2022-01-20. Retrieved 20 January 2022. {{cite web}}: |last= has generic name (help)