Basalt fibres

More recently basalt fibres have gained in popularity. The basic material is natural basalt stone (with a composition of at least 50% Si02) which is then treated using a pyrolytic process (similar to the carbon fibre). The main challenge during the production process is to eliminate the high quantities of iron impurities (FeO or Fe203) in the basalt mineral. Basalt fibres can be used in all types of resins (epoxy, phenol, polyester). 

FEM analysis will establish the approximate thickness of carbon-fibre panelling required to meet overall stress requirements (expressed in g/m ). It will also establish the quality of carbon fibres required (expressed typically in terms of HT(A/S), UM, etc.) as well as their orientation (e.g. single-or multi-directional layer). Further analysis will identify in which areas the carbon-fibre thickness can be reduced to 50% if required, with local reinforcements applied to meet stress levels. This analysis can also help establish where carbon-fibre composites can be replaced by basalt-fibre composite components. As an example, FEM analysis would reveal that, based on the chosen wall design concept, a 4 x 400 g/m multi-layer carbon HT-fibre would achieve the required strength. It would also highlight those areas which would need... 

FIGURE 3. Images of silicate fibre-reinforced soda-lime glass matrix composites demonstrating their light transmittance and transparency (a) basalt fibre, (b) AR-glass fibre reinforcement [99]. 

There are a range of other inorganic fibres, such as basalt fibres (e.g. Basaltex , Marureel, Belgium) from a naturally-occurring complex silica/ alumina/other oxide basalt rock similar to glass in composition, used as an asbestos-replacement and available in filament and non-woven forms with claimed superiority to glass fibres in terms of temperature performance (see Table 4.2). 

Cellulose Basalt fibre Glass fibre Carbon fibre Aramid... 

In principle, all fibres available for FRP can also be used as reinforcement in prepregs, the most common ones being carbon and glass fibres. Polymeric fibres made from aramid or polyethylene are also quite coimnon, as are inorganic basalt fibres, or natural fibres like hemp or flax. Often, the fibres are directly impregnated to make unidirectional (UD) tapes. Alternatively, they can first be transformed into fabric products, such as woven fabrics or non-crimp fabrics (NCF), and then impregnated to create multi-directional prepregs. 

In terms of eonstituent materials, new types and forms of fibre reinforcements are likely to be introduced. In relation to this it is worth mentioning basalt fibres as an emerging alternative to the reinforcement of FRP pultruded composites. Although the manufacturing cost of basalt fibres currently exceeds that of E-glass fibres (Ross, 2006), the mechanical properties of... 

Lopresto V, Leone C and De lorio I (2011), Mechanical characterisation of basalt fibre reinforced plastic . Composites Part B Engineering, 42(4), 717-723. 

Dias, D.P.,Thaumaturgo, C.,2005. Fracture toughness of geopolymeric concretes reinforced with basalt fibres. Cement Concrete Composites, 27(1), pp. 49-54. 

Storage modnlus of PP-wood composites [80], basalt fibre-reinforced PP [88], ethylene-propylene-diene terpolymer [89], polyvinyl fluoride-clay nanocomposites [90], thermosetting resins [91], and water-based adhesives [81, 82]. 

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