Density Measurement

Fibre density provides an indication of the progress of chemical reactions during the conversion of PAN precursor into carbon fibre. It is a relatively simple property to measure and provides rapid feedback regarding the progress of the stabilisation and carbonisation process at any location along the processing line. At Carbon Nexus we measure fibre density using two different methods:

Gas pycnometry

Gas pycnometry is a method by which the volume of a sample of fibre may be determined by measuring the amount of gas which the fibre sample displaces under controlled conditions. Then, knowing the volume of a sample of a known length, the linear density of the fibre may be calculated.

Density gradient method

A sample of fibre is immersed into a liquid column containing a known and calibrated density gradient and allowed to descend through the column. The position at which the sample floats due to its neutral buoyancy indicates the density of the sample.