%A WANG Miao, WANG Wei, YANG Yunlong, TAN Caiwang, WANG Gang %T Effect of brazing time on microstructure and properties of SiC ceramic brazed with CoFeNiCrCu %0 Journal Article %D 2022 %J Acta Aeronautica et Astronautica Sinica %R 10.7527/S1000-6893.2021.25057 %P 525057-525057 %V 43 %N 4 %U {https://hkxb.buaa.edu.cn/CN/abstract/article_18451.shtml} %8 2022-04-15 %X The SiC ceramic was brazed by CoFeNiCrCu filler, and the effect of brazing time on the microstructure and mechanical properties of the joint was investigated. The results show that the typical interface structure of the joint is SiC/Cr23C6+Cu(s, s)+Si(s, s)/HEAF+Cu(s, s)/Cr23C6+Cu(s, s)+Si(s, s)/SiC. With the increase of brazing time, no change of types of phases occurred in the structure; the joint was still mainly composed of solid solution due to the high entropy effect, but the thickness of the reaction layer in the joint gradually increased. When the brazing time was 90 min, the thickness of the reaction layer reached a maximum of 25 μm. However, the stress generated during the cooling process of the over thick reaction layer joint was concentrated in the reaction layer and caused defects such as cracks in the reaction layer. When the welding temperature was 1 180℃ and the holding time was 60 min, the maximum joint shear strength reached 61 MPa. At this time, cracks started from the SiC ceramic of the extended joint, and then expanded in the direction of the joint, and finally ruptured at the interface between the ceramic and the reaction layer.