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However, there are two critical factors hindering its application: first, a high level of boron (about 66 at.

%) leads to severe loss of material under the scouring of hot gas because of the rapid evaporation of boron oxides at temperatures above 1,200 °C (refs 9, 10), second, monolithic Zr B to form multi-phase ceramics.

The carbide is a substitutional solid solution of Zr–Ti containing carbon vacancies that are randomly occupied by boron atoms.

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More broadly, this work provides a platform for building a series of UHTCs based around the group IV/V transition metals.

coating on C/C composite alongside other common UHTCs and composites.

Hence, the MAR and LAR results for our carbide in Fig.

1 demonstrate a significant improvement in ablation resistance relative to existing UHTCs coatings or composites as well as monolithic Zr B in weight.

The dots are the volume percentage of each phase calculated from each virtual slice. The zig-zag shape of the dot is due to the alternating plies. Figure 2 shows a photograph of the ablation test and the morphology of the tested sample.

The grey area represents the top of the sample which has been excluded from quantification due to strong artefacts. Despite the low level of boron present, our carbide displayed the characteristic light green flame during the ablation test, which in contrast to the carbide (that is, Zr C. 2b,c, the ablated surfaces are relatively smooth and free from any obvious erosion hollows and cracks.The mass ablation rate (MAR) and linear ablation rate (LAR) characterize the mass loss and dimensional stability of the materials, respectively.In general, a high MAR (that is, rapid loss of mass) and LAR (that is, rapid degradation of surface integrity) indicate poor ablation performance.Wang Haiyan (Peking University First Hospital), PUMC and NKF gathered with 44 of China’s leading nephrologists in Shanghai to launch the Chinese commentary on KDIGO’s CKD-MBD clinical guideline. The China Working Group then separated into groups defined by geographical region, and discussed with their constituents CQI implementation strategy for their local dialysis centers.Ultra-high temperature ceramics are desirable for applications in the hypersonic vehicle, rockets, re-entry spacecraft and defence sectors, but few materials can currently satisfy the associated high temperature ablation requirements.By contrast relatively little attention has been directed towards the development of a single-phase ceramic comprising multiple elements.

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