Accurate analysis of carbon fibre composites

Paul Boughton

Exeter Analytical, specialists in elemental microanalysis, has developed proprietary techniques based on its Model 440 CHN analyser to enable accurate determination of per centage carbon (C) and hydrogen (H) in carbon fibre composite materials.

Carbon fibre analysis is of great interest to developers of products that benefit from the unique strength to weight ratio and rigidity of carbon fibre reinforced materials - often referred to as carbon fibre composites.  Applications for carbon fibre composites include aerospace, marine craft, Formula 1 and high-end automobiles, bicycles, sports equipment and firearms manufacture.

With this wide range of applications comes the need for accurate carbon fibre/composite materials analysis. The Model 440 with its unique horizontal combustion furnace design is perfect for the analysis of such materials. CHN analysis can be routinely carried out on these materials with unsurpassed accuracy and precision.

Carbon fibres are extremely difficult to completely combust and therefore analyse due to their very high melting points. Exeter Analytical has made = advances in accurately analysing Carbon fibre composites on the Model 440 which employs a pure oxygen static combustion method to fully combust samples. Carbon fibre composite materials need to be given time to fully combust, flash combustion alone is not good enough and can frequently lead to memory effects from uncombusted material. This is a common problem with vertical combustion CHN microanalysis systems which do not remove residue between each analysis. Benefiting from its unique horizontal furnace design, and software that enables complete control over combustion parameters, the Model 440 will achieve 100 per cent combustion of carbon fibre samples and remove the residue between each analysis.