Damage behavior of atomic oxygen on a hafnium carbide-modified C/ SiC composite

Capability of a HfC-modified C/SiC (C/SiC-HfC) composite against high-speed atomic oxygen (AO) atoms was evaluated in a ground-based low Earth orbit simulating system. Energy Dispersive Spectrum, Scanning Electron Microscopy, X-Ray Diffraction and Raman spectroscopy were employeed to investigate the damage behaviors of the material. The results show that HfC was oxided by AO preferentially, while HfO2 and graphite films were its main products during AO exposure. The crystallization degree of the graphite film increased with the increasing of AO total flux. It's found that SiC areas had lower surface damage than HfC areas, and SiO2 was its main reacting product. Ascribed to the evolution of surface craters, three-point bending strength of the specimens increased within the first 10 h exposure of AO and decreased thereafter. The damage mechanisms of AO over C/ SiC-HfC were revealed also.

Automated summary

A ground-based evaluation was conducted on the resistance capability of a HfC-modified C/SiC composite against high-speed atomic oxygen in a low Earth orbit simulating system. Various analytical techniques were used to investigate the damage behaviors, products, and mechanisms of the material exposed to atomic oxygen. The study revealed that the material exhibited different responses in different areas, with HfC areas oxidizing preferentially and SiC areas showing lower surface damage.