陶瓷/金属钎焊体系反应润湿及残余热应力缓解的研究进展

Reactive Wetting and Thermal Residual Stress Releasing of Ceramic/Metal Brazed Joints:A Review

陶瓷/金属钎焊件广泛应用于机械电子、能源化工、航空航天和生物医学等领域以实现材料各自性能上的优势互补。然而,陶瓷与金属原子键合上的差异及热膨胀失配使得它们的高可靠连接面临润湿性和残余热应力的问题。综述了国内外在反应润湿和残余热应力缓解方面的研究进展,对活性钎料/陶瓷界面反应产物及界面结构、界面反应热力学、反应润湿及铺展动力学模型进行了介绍,总结了复合钎料法和添加中间层法等残余热应力的缓解方法,并对当前存在的问题进行了初步探讨。

Ceramic/metal brazed assemblies are widely used in mechanical and electronic engineering, energy and chemical industry, aerospace and biomedical fields to make their respective advantages complementary to each other. However, the differences in interatomic bonds and thermal expansion coefficients between ceramics and metals make them hard to be jointed together reliably because of the poor wettability of ceramics and thermal residual stress produced during the brazing process in the ceramic/metal joints. This article overviews the research progress on the reactive wetting of the liquid metals on ceramics and the methods of redu- cing the residual stress levels in the joints. The interfacial reaction products, interracial structure, reaction thermodynamics, reactive wetting and spreading dynamics models of active brazing alloy/ceramic systems are introduced. The stress relief methods of composite fillers and adding interlayer are summarized. The fundamental issues of reactive wetting and the disadvantages of current stress relief methods are discussed.