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Carbon rods

Ultra high purity carbon rods are used for carbon evaporation in EM applications to either coat non-conductive specimens with a thin layer of carbon or to produce support films for TEM specimens. The structure of the carbon rods is high purity graphite which is formed during the purification process of the rods. The maximum level of impurity for  high-purity carbon rods is 2ppm with none of the elements exceeding 1ppm. See typical statements of purity. The typical level of impurity is 1ppm or less. This makes ultra-high purity carbon rods ideal for SEM/EDS, EBSD, WDS and EPMA applications. Two grades of ultra-high purity carbon rods are offered:

Grade F-S high-purity standard grade

This is the most common grade of carbon rods. The rods tend to be stronger and more brittle. Stepped points of this grade are best made with an electrical carbon rod shaper. Available in Ø3.05mm (Ø0.120”) and Ø6.15mm (Ø0.242”) with a length of 305mm (12”). Compatible with carbon coaters from Cressington, Agar Scientific, JEOL, Quorum Tecnologies, Leica, Edwards, Anatech (Hummer) and Denton.

Grade F-A high purity softer grade

This is a softer grade and stepped points are somewhat easier to make from this grade, when using a hand-held carbon rod shaper.  Compatible with coaters from Cressington (50Hz), Agar (50Hz), JEOL (50Hz), Edwards and Denton.

Carbon rod shaper for 6.15mm diameter rods

Please see Ordering Information below for details.

For carbon fibre cord see this link.

Specification: ultra-high purity carbon rod grades

Parameter Grade F-S Grade F-A
Density (g/cm3) 1.80 1.61
Electrical resistivity (µOhm.cm) 939.7 635
Hardness (shore) 42 32
Porosity (%) 16.5 28.5
Tensile strength (MPa) 41.4 22.1
Flexural strength (MPa) 51.8 24.2
Compressive strength (MPa) 65.6 48.2
Thermal expansion rate (x10-6/K) 2.9 1.9
Purity Ultra-high Ultra-high
Impurities (ppm) Max. 1/element Max. 1/element
Structure Graphite Graphite
Appearance Hard, brittle Softer


Carbon rods ordering information: