Abrasion carbon fibres

Intended for high-performance applications because of their cost, carbon fibres have excellent mechanical properties but are sensitive to impact and abrasion. They are used for their attractive characteristics, such as ... 

Physical and thermal properties Polyesters are formed via a condensation reaction. PET and poly(butylene terephthalate) (PBT) are not crosslinked so are thermoplastic, but cured polyesters are crosslinked and thermosets. Polyesters may be reinforced with glass or carbon fibres or particles. Addition of 30% or more carbon fibre induces electrical conductivity in polyesters. Despite its high polarity, PET Is a good electrical insulator at ambient conditions because its Tg is considerably higher than room temperature. Polyesters have good abrasion resistance and are tough. PET is impervious to water but has low permeability to oxygen. 

This is a thermoplastic material, the correct name for which is poly-etheretherketone. PEEK is also regarded as a high-performing polymer, offering excellent chemical resistance, very low moisture absorption and good wear, abrasion and electrical resistance. It can be used continuously to 250°C in hot water and steam without permanent loss in physical properties. It is used to replace metal parts in the aerospace, automotive, oil and gas industries and is available reinforced with glass and carbon fibre. 

Wielage B, Domer A, Wear behaviour of carbon fibre aluminium-composites during abrasive loading, Praktische Metallographie-Practical Metallography, 35(7), 350-358, 1998. 

Inorganic fibre Carbon fibre pitch / ++ (poor abrasion) ++ ++... 

Finally, Buchman et al. [72] have evaluated the use of excimer laser treatment of carbon fibre reinforced PEEK composites. Once again, the final performance of the bond depended on the intensity of the pretreatment but these workers quoted that the resultant adhesive strengths were nearly double those for conventionally pretreated (hand-abrasion) substrates. 

UHMWPE fibre has good strength and specific rigidity with toughness and abrasion resistance. It can be used to make rackets, surfboards and snowboards. For its flexibility and light weight, it can be compared with carbon fibre. 

Carbon and glass fibres are very abrasive and quickly wear away high-speed steel tools. For intensive use, carbide or diamond tools are preferable. 

Other applications are found in powder technology. The cohesion in pellets formed out of dry powders can be improved by treating the powder with an appropriate polymer solution. This process is used on an enormous scale to prepare iron ore in a form suitable for blast furnaces, but also for the preparation of pharmaceutical specialty products. Polymers are applied at a large scale in paper-making where they help to strengthen the network of celluloslc fibres and to trap different kinds of particles in this network. The building of a network Is also the purpose of adding carbon black to rubber, which improves its resilience and abrasive resistance. 

Limitations of PTFE are its poor abrasion resistance, high coefficient of expansion and poor thermal conductivity. By adding filler materials such as glass fibre, carbon and finely powdered metal, these characteristics can be modified and improved. 

Thus, substrates such as aluminium and its alloys, alloys of titanium, low- and high-carbon steels, nickel, copper, fibre-reinforced plastics (containing both thermoplastic and thermosetting matrices - in the latter case, the matrix might well also be a formnlated epoxy-based system), glass, concrete and wood are all encountered. This means that they can be, and indeed are, widely used in construction, aerospace, automotive (both original equipment and aftermarket), electrical and electronics, furnimre, foundry, consumer and abrasives applications. 

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