几种钴基高温钎料对SiC陶瓷的润湿与界面结合

THE WETTING OF SEVERAL HIGH-TEMPERATURE BRAZING FILLERS ON SiC CERAMIC AND INTERFACIAL BONDING

采用座滴法研究了几种钴基合金在ＳｉＣ陶瓷上的润湿行为，结果表明，在 １４９３ Ｋ－１０ｍｉｎ的真空加热条件下，设计的 ＣｏＦｅＮｉ（Ｓｉ，Ｂ）－（８—１５）Ｃｒ－（１４—２１）Ｔｉ合金能较好地润湿ＳｉＣ陶瓷，但合金与ＳｉＣ之间发生了十分强烈的界面反应，在靠近ＳｉＣ约１１５ｕｍ的范围内，主要是钎料中元素Ｃｏ，Ｆｅ，Ｎｉ，Ｃｒ参与反应，而在距离ＳｉＣ表面稍远的区域则形成了ＴｉＣ反应带，分析了其原因 新设计的 ＣｏＮｉ（Ｓｉ；Ｂ）－（８—１５）Ｃｒ－（１４—２１）Ｔｉ与 ＳｉＣ 陶瓷之间发生了适度的界面反应．能实现合金／陶瓷界面的牢固结合；商用钴基钎料ＢＣｏ１虽然能很好地润湿ＳｉＣ，但由于钎料自身脆性大，试样冷却后在ＳｉＣ陶瓷内部发生断裂。

The wetting behavior of several Co based alloys on Sic was studied by the sessile drop method. The results show that under the vacuum condition of 1493 K-10 min, good wettability can be obtained by the CoFeNi(Si, B)-(8-15)Cr-(14-21)Ti alloy, but undue reactions occurred at the interface. The elements Co, Fe, Ni and Cr in the brazing alloy participated in the interfacial reactions within the width of 115 mum close to the SiC surface, and the reaction band of Tic formed in the zone further away from the Sic. The newly-designed CoNi(Si, B)-(8-15)Cr-(14-1)Ti alloy exhibited good adhesion with the Sic ceramic because of suitable interfacial reactions. Though the contact angle of the commercial Co-based filler metal BCo1 on Sic was small (20 degrees), the fracture occurred within the Sic and the brazing alloy cracked into fragments.