工艺参数对SiC陶瓷热压反应连接强度的影响  

Effects of Technological Parameters on the Joining Strength of SiC Ceramic by Hot Pressing Reaction Welding

作　　者：张建军[1] 李树杰[1] 段辉平[1] 刘勇[1] 张艳[2] 

机构地区：[1]北京航空航天大学,北京100083 [2]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《稀有金属材料与工程》2003年第7期542-545,共4页Rare Metal Materials and Engineering

基　　金：中国航空基础科学基金;国家自然科学基金资助项目(50271003)

摘　　要：采用Ag粉和Ti粉作为焊料,对再结晶SiC陶瓷进行热压反应连接。研究了2种工艺,其中工艺1与传统的扩散焊工艺相似,即分别在不同的焊接温度下保温一定的时间;而工艺2则是首先在某一较高温度下进行短时间的保温,以利于Ti与SiC母材发生适度的界面反应,促进界面结合,同时液相银的出现将显著缓解焊接应力,随后在另一相对较低的温度下保温较长时间,以利于Ag-Ti金属间化合物的形成,有利于提高接头的焊接强度和工作温度。结果表明,采用工艺2获得的接头抗弯强度较高,达到SiC陶瓷母材强度的73.4%。微观结构研究表明,在界面处生成了反应层,焊料产物主要由两种相相间组成。EDX分析结果表明,界面处发生了元素的互扩散。SiC ceramic can be used for manufacturing the parts serving at elevated temperature and in chemical environment in many areas due to its attractive thermo-chemical and thermo-mechanical properties. However, the wide applications of SiC normally depends on the joinings of the ceramic material to itself or to other metallic materials. In this study, the joining of recrystallized SiC ceramic to itself has been realized by a hot pressing reaction welding with the particulate filler composed of Ti/Ag/Ti. The joining experiments were conducted by employing a Gleeble 1500 thermo-mechanical testing machine. Two welding processes were experimentally studied. The first one is similar to the typical diffusion welding process, and the second one is designed on the consideration that the moderate interfacial reactions take place to facilitate the interfacial bonding and the proper intermetallics form in the filler to improve the welding strength and to increase the working temperature of the joints, also a appropriate liquid phase appears in the filler during welding to relax the thermal stress. The experimental results show that the bending strength of the joint obtained by the second process is higher than that by the first process. Up to be 73.4% of the SiC at room tempetature under the technological parameters of 1 030degreesC for 300 s, then at 970degreesC for 900 s before cooling down to room temperature. Microstructural studies reveal that the welded area is mainly composed of two phases analyzed by EDX. The experimental results indicate that the interdiffusion takes place at the interfaces during welding.

关 键 词：陶瓷连接 SIC陶瓷 热压反应烧结连接 

分 类 号：TQ174[化学工程—陶瓷工业]