A novel Y₃Si₂C₂ material was synthesized at a relatively low temperature (900 °C) using a molten salt method for the first time, and subsequently used as the joining material for carbon fiber reinforced SiC (C_f/SiC) composites. The sound near-seamless joints with no obvious remaining interlayer were obtained at 1600 °C using an electric field-assisted sintering technique (FAST). During joining, a liquid phase was formed by the eutectic reaction among Y₃Si₂C₂, γ(Y—C) phase, and SiC, followed by the precipitation of SiC particles. The presence of the liquid promoted the sintering of newly formed SiC particles, leading to their complete consolidation with the C_f/SiC matrix. On the other hand, the excess of the liquid was pushed away from the joining area under the effect of a uniaxial pressure of 30 MPa, leading to the formation of the near-seamless joints. The highest shear strength (τ) of 17.2±2.9 MPa was obtained after being joined at 1600 °C for 10 min. The failure of the joints occurred in the C_f/SiC matrix, indicating that the interface was stronger than that of the C_f/SiC matrix. The formation of a near-seamless joint minimizes the mismatch of thermal expansion coefficients and also irradiation-induced swelling, suggesting that the proposed joining strategy can be potentially applied to SiC-based ceramic matrix composites (CMCs) for extreme environmental applications.

首次采用熔盐法在较低温度（900 ℃）下合成了一种新型Y ₃ Si ₂ C ₂材料，随后用作碳纤维增强SiC（C _f /SiC）复合材料的连接材料. 使用电场辅助烧结技术 (FAST) 在 1600 °C 下获得了无明显残留夹层的良好的近无缝接头。_{在接合过程中，Y 3} Si ₂ C ₂、γ之间的共晶反应形成液相(Y—C) 相和 SiC，然后是 SiC 颗粒的沉淀。液体的存在促进了新形成的 SiC 颗粒的烧结，导致它们与 C _f /SiC 基体完全固结。另一方面，在 30 MPa 的单轴压力的作用下，多余的液体被推离连接区域，导致接近无缝接头的形成。在 1600 °C 下连接 10 分钟后，获得了 17.2±2.9 MPa的最高剪切强度 ( τ )。接头失效发生在 C _f /SiC 基体中，表明界面比 C _f强/SiC 基体。接近无缝接头的形成最大限度地减少了热膨胀系数的不匹配以及辐射引起的膨胀，这表明所提出的连接策略可以潜在地应用于极端环境应用的 SiC 基陶瓷基复合材料 (CMC)。