Mechanical properties and thermal conductivity of lightweight and high-strength carbon-graphite thermal insulation materials

Abstract

Thermal insulation composites are widely used in civil and military applications; however, it is difficult to achieve the synergy of multiple technical objectives such as lightweight, thermal insulation, high pressure resistance and high-temperature resistance by adopting traditional preparation techniques. In this study, a novel carbon-graphite thermal insulation material was rapidly prepared by exploiting the micro-thermal press additive manufacturing forming technology, and these multiple objectives were simultaneously achieved by introducing a large number of closed pores. It was found that the percentage of closed pores in the carbon-graphite insulation was increased by increasing the forming density or the amount of thermosetting phenolic resin added, but the thermal conductivity increased in parallel with the compressive strength, while the addition of pre-covered expandable graphite was able to achieve the synergy of high compressive strength and low thermal conductivity. When the content of thermosetting phenolic resin was 25 wt%, forming density was 1.2 g·cm−3, and expandable graphite was clad twice, the prepared carbon-graphite insulation exhibited a closed porosity/porosity ratio, compressive strength, and thermal conductivity of 48.92%, 16.432 MPa, and 0.743 W·m −1 K−1, which has the advantages of lightweight, high compressive strength, heat insulation and high-temperature resistance and has good prospects for industrial applications.

New, 3d Binder-Jetted Carbons with Minimal Periodic Surface Structures

“…The mechanical properties of CLP and GY samples were found to be superior to those of compressed carbon-graphite composite (obtained by phenolic resin impregnation) with compressive strength ranging from 7 to 19.7 MPa at a density of 1.2 g cm − 3 [42]. In the context of 3D-printed carbon, CLP and GY (0.69 and 0.61 g cm − 3 , respectively) samples showed higher range of mechanical properties than porous carbon of similar density (about 0.55 g cm − 3 ) obtained by direct ink writing with compressive strength and Young's modulus values of 5.1 and 243 MPa, respectively [43].…”