SiC陶瓷的Ti-Si钎焊连接机理和性能研究

Mechanism and Properties of Ti-Si Brazing Joining Technique for SiC Ceramics

SiC陶瓷优异的力学性能、高温稳定性以及耐腐蚀等性能,使其在航空航天、海洋工程、核能领域具有极大的应用潜力。但是其高硬和高脆特性,使其很难通过加工实现大型复杂结构件的制备,从而限制了其在以上领域的应用。因此,低温、低压连接技术研究对促进SiC的应用具有重要意义。采用Ti-Si钎料对CVD-SiC母材在1450℃~1550℃进行无压连接,结果表明,在1500℃连接时接头剪切强度最佳,此时剪切强度为(23.1±5.7) MPa,SiC接头断裂时发生在连接层和界面处。

SiC ceramics have excellent mechanical properties, high temperature stability and corrosion resistance, thus having great application potentials in the fields of aerospace, marine engineering and nuclear energy. However, due to their intrinsic brittleness and high hardness, it is difficult to obtain SiC ceramic components with large and complex shape by machining. It is, therefore, important to develop low-temperature and low-pressure joining technologies to extend the applications of SiC ceramics. Ti-Si filler was used as interlayer to join the CVD-SiC matrix at the temperatures ranging from 1450 ℃ to 1550 ℃ for pressureless joining. The results revealed that the SiC joint, which was joined at 1500 ℃, had the highest shear strength(23.1±5.7)MPa. Simultaneously, the fracture of the joint occurred both on the interlayer and interface.