Resin-bonded SiC-Al-Si composite was prepared and sintered under flowing nitrogen at 1600℃. By adjusting the Al/Si ratio, the controllable synthesis of various non-oxide reinforcing phases was achieved. The phase evolution mechanism was revealed, providing a theoretical foundation for the production and application of novel SiC-based refractory. As flowing nitrogen contained traces of oxygen, both Al and Si in the surface layer of the samples may be oxidized and nitrided. As the Al/Si mass ratio increased, the phase evolution in the surface layer of sintered samples followed this sequence: Si5AlON7→Si3Al3O3N5+AlN-SiC solid solution→AlN-SiC solid solution +Al2O3→Al7O3N5+Al2O3. As Al and Si consumed oxygen and generated non-oxides with multi-morphic sealed pores in the surface layer, the inner layer remained oxygen-free and low-nitrogen, leading to different phase evolution. As the Al/Si mass ratio increased, the phase evolution in the inner layer followed: Si3N4→AlN-SiC solid solution→AlN-SiC solid solution (content increase)→Al4SiC4. The synergistic toughening of various non-oxide resulted in a cold crushing strength of sintered samples exceeding 150 MPa. A reaction model was established.

中文翻译：

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1600℃流动氮气下SiC-Al-Si复合材料的相演化机制


制备了树脂结合SiC-Al-Si复合材料，并在流动氮气下于1600℃下烧结。通过调节Al/Si比例，实现了多种非氧化物增强相的可控合成。揭示了相演化机理，为新型碳化硅基耐火材料的生产和应用提供了理论基础。由于流动的氮气中含有微量的氧，样品表层的Al和Si都可能被氧化和氮化。随着Al/Si质量比的增加，烧结样品表层的相演化遵循以下顺序：Si5AlON7→Si3Al3O3N5+AlN-SiC固溶体→AlN-SiC固溶体+Al2O3→Al7O3N5+Al2O3。由于Al和Si消耗氧并在表层生成具有多形态密封孔的非氧化物，而内层保持无氧和低氮，导致不同的相演化。随着Al/Si质量比的增加，内层相演化顺序为：Si3N4→AlN-SiC固溶体→AlN-SiC固溶体（含量增加）→Al4SiC4。多种非氧化物的协同增韧使得烧结样品的冷压碎强度超过150 MPa。建立了反应模型。