Multi-scale study of high-strength low-thermal-conductivity cement composites containing cenospheres

Abstract

Cenosphere particles are hollow, but due to their hard shells, they can be used in cementitious composites to produce ultra-lightweight cement composites (ULCC) with high strength and low thermal conductivity. This study integrates thermal conductivity with mechanical experimental research, microscopic investigation, and numerical simulations to provide new insights into the behavior of these advanced composites. The microstructure of ULCC samples was characterized using synchrotron high-resolution microtomography, transmission electron microscopy and scanning electron microscopy. Composite models were used to predict the thermal conductivity of the cenospheres based on the experimental results of ULCC thermal conductivity and the porosity of the samples.

Influence of cenosphere on tribological properties of short carbon fiber reinforced PEEK composites

“…However, a lower friction coefficient was obtained with the increase of load for PEEK/SCF and PEEK/SCF/CS composites, which may be due to the good thermal conductivity of carbon fiber and cenosphere. Carbon fiber or cenosphere can help conduct heat of the frictional contact surface in time, the surface temperature is relative lower compared with PEEK, then there is no serious adhesive wear (see Figure ) of PEEK composites under high load . Here, in this case, the former of the two competitive actions takes over the dominant position.…”

Effect of SiO2 nanoparticles‐decorated SCF on mechanical and tribological properties of cenosphere/SCF/PEEK composites

“…The reason is that the shear strength of pure PEEK resin decreases under high load, and serious adhesion wear occurs on the surface during friction, which increases the friction coefficient. For CS/SCF/PEEK and CS/SCF‐SiO 2 /PEEK composites, a positive rolling effect of micrometer‐sized CS and nano‐SiO 2 particles between the material pairs reduced the stress concentration on the fibers, while SCF could reduce the friction heat on the wear surface to avoid the phenomenon of severe adhesion . Eventually, the friction coefficient was reduced.…”

“…For CS/SCF/PEEK and CS/SCF-SiO 2 /PEEK composites, a positive rolling effect of micrometer-sized CS and nano-SiO 2 particles between the material pairs reduced the stress concentration on the fibers, while SCF could reduce the friction heat on the wear surface to avoid the phenomenon of severe adhesion. [28][29][30] Eventually, the friction coefficient was reduced. Figure 8(b) shows that the specific wear rate of pure PEEK and CS/SCF/PEEK composites increases with the increase of load, while the friction coefficient of CS/SCF-SiO 2 /PEEK composites decreases slightly with the increase of load.…”

Sunlight Permeability of Translucent Concrete Panels as a Building Envelope

“…It is noteworthy that compliance with building code requirements was assumed in the selection of the building materials used. The TCP was recently manufactured at the University of California, Berkeley, California, as precast units using white ultralightweight cement composites (ULCCs) for an aesthetically appealing solution with low thermal conductivity (Rheinheimer et al 2017) and involving polyethylene fibers for control of tensile stresses. The following subsections explain the different studies for Layer B of the panels.…”