Effects of fibre content on mechanical properties and fracture behaviour of short carbon fibre reinforced geopolymer matrix composites

Abstract

Geopolymer matrix composites reinforced with different volume fractions of short carbon fibres (C f /geopolymer composites) were prepared and the mechanical properties, fracture behaviour and microstructure of as-prepared composites were studied and correlated with fibre content. The results show that short carbon fibres have a great strengthening and toughening effect at low volume percentages of fibres (3⋅5 and 4⋅5 vol.%). With the increase of fibre content, the strengthening and toughening effect of short carbon fibres reduce, possibly due to fibre damage, formation of high shear stresses at intersect between fibres and strong interface cohesion of fibre/matrix under higher forming pressure. The property improvements are primarily based on the network structure of short carbon fibre preform and the predominant strengthening and toughening mechanisms are attributed to the apparent fibre bridging and pulling-out effect.

Preparation and mechanical performance of Cf-SiCf-(Al2O3p) reinforced geopolymer composites

“…The short carbon fiber reinforced showed good mechanical properties with non-brittle failure behavior [21]. The SiC fiber exhibited similar mechanical properties as carbon fiber, and much higher oxidation resistance [24], which makes it a prominent high-temperature reinforcing candidate.…”

“…Timakul et al [20] reported the addition of basalt fibers into the fly ash-based geopolymer can improve its compressive strength. Lin et al [14,[21][22] prepared the short carbon fiber geopolymer matrix composites using sheetlike fiber preform, and improved the mechanical properties. The addition of α-Al 2 O 3 particles into the composites could reduce the volume change of the composites and improve the mechanical properties, especially at high temperatures [22].…”

“…In our previous research, we have attempted short carbon fiber and SiC fiber reinforced geopolymer composites, respectively [21][22]23]. The short carbon fiber reinforced showed good mechanical properties with non-brittle failure behavior [21].…”

A Novel MK-based Geopolymer Composite Activated with Rice Husk Ash and KOH: Performance at High Temperature

“…By bridging cracks, a wide range of polymeric, mineral and natural fibres have been used to improve geopolymer tensile and flexural strength, toughness, and energy absorption capacities (35). Short fibres of polypropylene (PP) (36,37), polyvinyl alcohol (PVA) (38), basalt (39,40), glass (41,42), carbon (43,44), alumina (45,46) and steel (47) have been successfully incorporated into geopolymers at volume fractions between 0.5-3.5%. Higher fibre contents, up to 20% (44), provide more control over cracking and increase mechanical strength of the brittle matrix.…”

Effect of curing time on microstructure and mechanical strength development of alkali activated binders based on vitreous calcium aluminosilicate (VCAS)

“…As can be observed in the literature (Komnitsas and Zaharaki 2007;Pacheco-Torgal et al 2008a), the geopolymerization process depends essentially on three factors: alkaline solution, alumino-silicate source material and curing conditions. The most common alumino-silicate source materials used in the geopolymerization process are slags (Puertas et al 2000;Bernal et al 2011), metakaolin (Lin et al 2009;Marín-López et al 2009;Zivica et al 2011) and fly ashes (Fernández-Jiménez et al 2005;Lloyd et al 2009). However, in the last years, the use of different alumino-silicate materials have been performed: natural pozzolans (Xu and van Deventer * Author for correspondence (jjpaya@cst.upv.es) 2000; Najafi Kani et al 2012), tungsten mine waste (PachecoTorgal et al 2008b, c), ceramic waste (Puertas et al 2006;Reig et al 2010), FCC catalyst residue construction and demolition waste (Lampris et al 2009;Payá et al 2012).…”