Microstructure and properties of SiCf/SiC composite joints with CaO–Y2O3–Al2O3–SiO2 interlayer
| Autor: | Laifei Cheng, Biao Ji, Chenghua Luan, Le Wang, Shangwu Fan, Juanli Deng, Shaobo Yang, Bohan Zheng |
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| Rok vydání: | 2021 |
| Předmět: |
010302 applied physics
Materials science Process Chemistry and Technology Sintering Mullite 02 engineering and technology 021001 nanoscience & nanotechnology Microstructure 01 natural sciences Cristobalite Thermal expansion Surfaces Coatings and Films Electronic Optical and Magnetic Materials law.invention law Phase (matter) 0103 physical sciences Materials Chemistry Ceramics and Composites Crystallization Composite material 0210 nano-technology Glass transition |
| Zdroj: | Ceramics International. 47:16603-16613 |
| ISSN: | 0272-8842 |
| DOI: | 10.1016/j.ceramint.2021.02.232 |
| Popis: | Using CaO, Y2O3, Al2O3, and SiO2 micron-powders as raw materials, CaO–Y2O3–Al2O3–SiO2 (CYAS) glass was prepared using water cooling method. The coefficient of thermal expansion (CTE) of CYAS glass was found to be 4.3 × 10−6/K, which was similar to that of SiCf/SiC composites. The glass transition temperature of CYAS glass was determined to be 723.1 °C. With the increase of temperature, CYAS glass powder exhibited crystallization and sintering behaviors. Below 1300 °C, yttrium disilicate, mullite and cristobalite crystals gradually precipitated out. However, above 1300 °C, the crystals started diminishing, eventually disappearing after heat treatment at 1400 °C. CYAS glass powder was used to join SiCf/SiC composites. The results showed that the joint gradually densified as brazing temperature increased, while the phase in the interlayer was consistent with that of glass powder heated at the same temperature. The holding time had little effect on phase composition of the joint, while longer holding time was more beneficial to the elimination of residual bubbles in the interlayer and promoted the infiltration of glass solder into SiCf/SiC composites. The joint brazed at 1400 °C/30 min was dense and defect-free with the highest shear strength of about 57.1 MPa. |
| Databáze: | OpenAIRE |
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