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Carbon fibre thread

High purity carbon fibre cord is specially manufactured for use in carbon evaporators or carbon coating attachments, widely used in scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The carbon fibre has undergone a specific purification heat treatment to remove impurities resulting in a spectroscopically pure carbon fibre (99.95%) with a maximum impurity level of 5-10 ppm, which is under the detection limit of EDS and/or WDS systems.

The carbon fibre is processed in strands, which are made into threads before being braided into carbon fibre cord. The carbon fibre cord should be cut to length and attached to the holding/clamping posts of the carbon evaporator head. Our carbon fibre cord resists unravelling at the ends when it is cut to length.

After evaporation the resulting carbon layer has similar properties to that produced from carbon rods. However, the thickness of the carbon layer depends on the thickness of the carbon fibre threads.
Power requirements are approximately 20V/20A (lower than for carbon rods) depending on carbon thread diameter, but can vary depending on brand and type of carbon coater.

Carbon fibre thread is available in three different diameters/weights:

  • Grade CT16 is a thicker carbon fibre thread with a diameter of 2.4mm and a weight of 1.6g/m. This is the most widely used carbon fibre thread. Recommended for carbon coaters made by Quorum, Emitech, EMS, SPI, Polaron, Fisons and Technics (Anatech/Hummer)
  • Grade CT7 is a medium carbon fibre thread with a diameter of 1.3mm and a weight of 0.7g/m. Grade CT7 is compatible with Leica ACE carbon coaters. Also used for applications where a thinner layer is required when using carbon coaters made by Quorum, Emitech, EMS, SPI, Polaron, Fisons and Technics (Anatech/Hummer)
  • Grade CT4 is a thin carbon fibre thread with a diameter of 0.8mm and a weight of 0.4g/m. Grade CT4 is recommended for very thin carbon coatings and for units with a smaller power supply. Grade CT4 shows better compatibility with carbon coaters made by Safematic, Leybold, Baltec, Balzers, Denton and Fullam

For thicker layers, the carbon fibre threads can also be double or tripled if the power supply in the carbon coater permits this.

For carbon rods see this link.

Specification of carbon fibre cord for carbon evaporation


Grade CT16 Grade CT7 Grade CT4

Diameter, mm

2.4 1.3 0.8

Weight, g/m

1.6 0.7 0.4

Resistivity, Ohm g/m2

20 20 20


High High High

Impurities (ppm)

5-10 5-10 5-10


Graphite Graphite Graphite


Flexible thread Flexible thread Flexible thread

Product #

70-CC1016 70-CC1007 70-CC1004

For carbon fibre on spools for Safematic CCU-010 carbon coaters, see: 300015

Ordering information: