• Verlag

High temperature stability (1100 -1500 degrees C) and oxidation behavior at 1500 degrees C of the SiOC/HfO2 ceramic nanocomposite were investigated in air. Consumption of free carbon dominated thermal stabilities of the bulk at below 1200 degrees C. Whereas, the continuous cristobalite scale, rather than HfSiO4, was responsible for the improved oxidation resistance at exceeding 1200 degrees C. At 1500 degrees C, HfSiO4, with maximum 30 vol. % concentration for duration of similar to 15 h, suffered ruptured spherical-bubbles by volatilized species and did not consolidate into a completely protective scale. Thus, the bulk exhibited limited resistance to oxidation at 1500 degrees C for long-term applications.

Shaanxi Provincial Education Department of China, Grant Number 2020JQ-170 2020TD-003, Fundamental Research Funds for the Central Universities, Grant Number G2019KY05116, Fund of Key Laboratory of National Defense Science and Technology in Northwestern Polytechnical University (NPU), Grant Number JZX7Y201911SY008901 6142911190207, National Natural Science Foundation of China (NSFC), Grant Number 51821091 51872246, NPU-TU Darmstadt Joint International Research Laboratory of Ultrahigh Ceramic Matrix Composites (JIRL), Key Laboratory of High Performance Ceramic Fibers of Ministry of Education (Xiamen University)