In addition, it has been shown that introducing such ceramics into carbon-fibre-reinforced carbon matrix (C/C) composites may be an effective way of improving thermal-shock resistance, laid down on a C/C composite by reactive melt infiltration (RMI) and pack cementation (PC) is proposed (Methods section and Supplementary Fig.1).The carbide comprises a substitutional solid solution with low boron content.
In general, a high MAR (that is, rapid loss of mass) and LAR (that is, rapid degradation of surface integrity) indicate poor ablation performance.
(c) Surface profile of central region of sample ablated at 3,000 °C, showing the ablated traces (some convexities with the rises of are quantified.
(b) Distributions of the phases from the top to the bottom of the sample determined from the X-ray computed tomography (CT) virtual slices.
It is noteworthy that the MARs of our carbide from 60–120 s at 2,000–2,500 °C distribute around the zero, indicating a slight weigh loss or weigh gain.
These higher negative values of LARs obviously distinguish it from other UHTCs indicated by the green arrows in Fig.
In addition, to improve the thermal-shock resistance, and to decrease the risk of cracking of the carbide coating during ablation, some carbides are allowed to infiltrate into the C/C composite.