Silicon carbide (SiC) is one of the hardest materials on Earth, used widely in abrasive blasting media and non slip products.
At 7 days compressive strength and thermal conductivity of cement-based composites reinforced with SiC were investigated. SiC was added physically without going through any new chemical reaction processes.
WC and SiC, when added individually or combined as hybrid components, significantly increased the density and flexural strength of concrete composites.
Compressive Strength
Silicon carbide (SiC) is an extremely hard ceramic material with excellent fatigue resistance, high thermal conductivity, low expansion coefficient and corrosion resistance properties. Due to this combination of properties it makes SiC an attractive material for use in concrete applications; for instance improving compressive strength by mixing into the mix; as a slip-resistant surface on concrete floors and increasing compressive strength during flotation processes or applied as dry shake. Furthermore, multiple trowelling sessions should ensure it’s securely embedded into the concrete mix.
Silicon carbide and tungsten carbide, two of the hardest materials on Earth, were studied for their effect on mechanical properties and permeability of concrete composites. Both kinds of carbides were added individually or collectively up to 4% of cement weight, and results showed both increased compressive and flexural strengths as well as increasing tensile quality significantly; both increased compressive strength slightly more than their respective competitors while simultaneously decreasing permeability substantially – leading to long term durability issues being reduced greatly with such additions.
The rapid chloride permeability test (RCPT) measures the permeability of concrete. According to results of this test, SiC and WC significantly improved its permeability compared with plain concrete, while the density of WC carbide composites resulted in maximum reductions; their synergy caused them to have lower permeabilities than plain concrete despite lower densities overall. Hybrid carbide composites had even lower permeabilities due to synergistic effects and better density characteristics of hybrid materials used together compared with plain concrete in terms of their density benefits compared to plain concrete in terms of their synergistic effect and better density provided by using hybrid materials in conjunction with plain concrete.
Flexural Strength
Flexural strength of concrete is a critical property that ensures its durability and resistance to cracking, according to researchers. They utilize various materials – fibers, polymers and admixtures – in order to increase this property of concrete; researchers often turn to materials such as silicon carbide which has various applications as an admixture in hard alloy metal waste products that feature unique characteristics like high strength, chemical stability and rigidity, making this an excellent option for applications involving heavy mechanical loads in harsh environments.
In this study, digital image correlation (DIC) and tensile testing were used to assess the flexural strengths of various cement-based composites. Results demonstrated that adding SiCw significantly delayed specimens from reaching peak stress values while increasing tensile strength to some extent; however, its presence decreased their ductility significantly.
This study explored the effects of various amounts and hybrid combinations of silicon carbide and tungsten carbide on concrete’s flexural and compressive strengths. A rapid chloride permeability test (RCPT) was also conducted; results demonstrated that hybrid carbide composites had higher flexural and compressive strengths compared to individual carbodies as well as being more suitable for concrete applications.
Density
Silicon carbide is an extremely hard and sharp material that can be embedded in concrete to produce slip-resistant surfaces. To do this, it must first be floated and troweled once before being distributed onto the surface in an even spread – approximately 25-50 pounds of material is typically broadcast and then worked into the concrete by light troweling; its sharp edges ensure it will stay at or near the concrete surface and create long-term slip resistance.
WC and SiC significantly enhanced both compressive strength and flexural strength of concrete composites, particularly their flexural strength – an issue often leading to durability issues and cracks. Furthermore, their addition reduced permeability significantly as it often had been an issue before.
Both WC and SiC have higher densities than concrete constituents, which might explain their substantial increase in density. Both materials also possess high intrinsic tensile/flexural strengths that enable them to transfer tension more efficiently than steel fibers in many investigations; additionally, both can also enhance fracture toughness – an integral aspect of durability for concrete structures.
Permeability
Permeability of concrete is a vital aspect of its durability, so optimizing its permeability is paramount to long-term performance. To enhance it further, silicon carbide (SiC) and tungsten carbide (WC) were added in various percentages to concrete composites at various levels; results demonstrated an increase in permeability with each incremented percentage; optimal results were seen at 4% of both individual and hybrid carbides combined together.
As carbide content increased, density also rose due to particle packing. Flexural strength also saw significant gains from adding carbide; making the concrete suitable for pavement applications. Tensile strength saw similar gains, likely as carbides are able to form strong matrix structures with cement that create stronger matrix networks.
SEM and EDS images and spectra of specimens modified with SiCw demonstrated that WC enhanced mechanical properties. When examined under an X-ray diffraction pattern, WC looked like solid metal with needle-like metallic luster that bridged cracks; no interlaminate zone (ITZ) appeared between cracks of this specimen and its fractured surface, showing it attracts hydration products.
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