RE_2O_3-Al_2O_3-SiO_2玻璃连接氮化硅合成复相陶瓷的研究

Bonding of Silicon Nitride Ceramic Composite with RE_2O_3 Al_2O_3 SiO_2 Glass Solders

采用Ｙ２Ｏ３Ａｌ２Ｏ３ＳｉＯ２Ｘ 稀土玻璃进行氮化硅复相陶瓷的连接。用四点弯曲方法测定不同连接工艺下的连接强度， 并对连接界面进行ＳＥＭ、ＥＰＭＡ 和ＸＲＤ 分析。液相钎料玻璃在界面上与氮化硅反应， 形成氮化硅／Ｓｉ２Ｎ２Ｏ／Ｙ（Ｌａ）Ｓｉａｌｏｎ 玻璃／Ｙ（Ｌａ）Ｓｉａｌｏ 玻璃的梯度层界面。接头强度随着保温时间、连接温度的增加， 先增后降。在ＹＡＳ钎料中添加氧化镧， 可以提高接头的高温强度。ＬａＹＯ３ 相的析出有利于接头高温强度的提高。

Liquid bonding of Si 3N 4 ceramic composite was carried out with RE 2O 3 Al 2O 3 SiO 2 glass solders. The effect of bonding conditions and interfacial reaction on the joint strength was studied. The joint strength under different bonding conditions was measured by four point bending tests. The interfacial microstructures were observed and analyzed by SEM, EPMA and XRD respectively. It is shown that the glass liquid solder reacts with Si 3N 4 at interface, and then the bonding interface with Si 3N 4/O′ Sialon/Y(La) Sialon glass/Y(La) Sialo glass is formed. The joint strength first increased with the increase of bonding temperature and holding time and reached a peak, and then decreased. According to microanalyses, LaYO 3 precipitated from joint glass can improve strength of joint at room and high temperatures.