Study on Correlation of Mechanical and Thermal Properties of Coal-Based Carbon Foam with the Weight Loss Rate after Oxidation

Abstract

With the increasing demand for high temperature-resistant heat insulation materials for hypersonic vehicles, carbon foam has been studied extensively, and its mechanical and thermal properties have been fully researched, but the oxidation behavior of carbon foams during service and the change in their properties after oxidation are rarely studied. This paper studied the relationship between both mechanical and thermal properties and oxidation degree of two kinds of foams, coal-based carbon foam and antioxidant coal-based carbon foam with chemical vapor deposition of SiC particles. The variation trend for the two kinds of foam was the same. When the oxidation degree was less than 15%, the compression modulus and strength weakened with the increase in weight loss rate, but the thermal conductivity decreased with the increase in weight loss rate, which was a favorable influence for the thermal protection system. The mechanical and thermal properties had a linear relationship with the weight loss rate, but the slope was different between 0% to 10% and 10% to 15%. The microscopic mechanism of these changes was also analyzed.

Study on Failure Criteria and the Numerical Simulation Method of a Coal-Based Carbon Foam under Multiaxial Loading

“…The production process of CCF used in this paper was introduced in our previous study [35]. Its mesoscopic structure is presented in Figure 1, which shows that the cells are approximately circular in the section perpendicular to the foaming direction and have higher ellipticity in the section along the foaming path.…”

Study on Low-Velocity Impact Performance of Coal-Based Carbon Foam Sandwich Structures in Thermal Protection Systems

“…Table 1 lists the mechanical and thermophysical properties provided by the manufacturer. The CCF's production process was introduced in our previous work [20], and Figure 2 shows its mesoscopic structure. It can be seen that the cells are approximately circular in the in-plane direction but elliptical in the out-of-plane direction.…”

“…(2) The high-temperature performance can be stable for a long time at 3000 • C under the condition of isolated air [18,19]. (3) The compressive modulus and strength are 1.5-2.5 GPa and 10-17 Mpa, respectively, at room temperature [19][20][21][22], and their reductions are less than 45% and 5%, respectively, at 1800 • C [23]. Compared with AETB's compressive modulus and strength, which are 0.153 GPa and 0.689 MPa [24], respectively, at room temperature, CCF's relatively high mechanical properties allow it to absorb more impact energy, which enable the TPS to withstand greater impact energy before overall or partial failure.…”