預金屬化和活性硬銲法製程對SiC/SiC接合件之強度與微結構研究

Abstract

陶瓷材料是一種具有優異性質之材料，但是因為脆性太高而限制其應用的範圍，因此需要適當的接合技術。其中預金屬化及活性硬銲法製程已廣泛應用於陶瓷材料與陶瓷材料間或陶瓷材料與金屬材料間之接合。本研究觀察用商業用Ag68.8Cu27.6Ti4.5銲料、自製Ag63.8Cu31.3Ti4.9銲料、自製Ag59.4Cu26.4In12.5Ti1.7及鍍Ti或Zr再用AgCu銲料硬銲而成之接合之微結構。並對接進行四點彎曲試驗評估所得接合之強度，討論微結構對強度之影響。 本研究所得之接合強度依序為商用AgCuTi銲料、自製AgCuTi銲料、鍍Ti再用AgCu銲料所作接合。至於AgCuInTi及鍍Zr再用AgCu銲料所作接合強度甚差，甚至在製作試棒時即發生斷裂。 對接合之微結構進行觀察商用AgCuTi銲料所形成之反應層有兩層，分別為TiC與Ti5Si3；自製銲料因為銲料元素不均勻的緣故造成反應層不均勻完整，主要是由Ti與C的反應物所組成。預金屬化接合因為Ti、Zr鍍層與SiC之間沒有產生一完整之反應層而強度不佳。AgCuInTi銲料所形成之反應層由Ti與Si所組成，雖然其反應層相當完整，但可能因反應層之物理性質不佳而影響接合強度。

Ceramic materials have excellent properties, but their brittleness limits the range of the application, so it needs proper joining technique to promote the use of ceramic materials. Pre-metallization and active brazing process have been widely used in the joining of ceramic-ceramic or ceramic-metal materials. The microstructures of SiC/SiC joints brazed with commercial Ag68.8Cu27.6Ti4.5、home made Ag63.8Cu31.3Ti4.9、Ag59.4Cu26.4In12.5Ti1.7 filler metals and pre-coating Ti or Zr SiC brazed with AgCu filler metal were examined. The strength of the joints according to the four point test result was determined. Then the relationship between the microstructure and the strength of the joints was discussed. The joining strength in this study is in the following order : commercial AgCuTi filler metal joints > home made AgCuTi filler metal joints > pre-coating Ti then brzaed with AgCu filler metal joints. The joints made with the AgCuInTi and pre-coating Zr then brazed with the AgCu filler metal have very poor join strength, they even break in the process of preparing the specimen. Through the observation of the microstructure of the joints, it was found that the joints made by the commercial AgCuTi filler metal form two reaction layers TiC and Ti5Si3. Because the elements in the home made AgCuTi filler metal were not uniform, the reaction layer was not uniform and complete, mainly composed by the Ti and C reaction products. Joints made by the premetallization process did not have good bonding strength, because Ti, Zr coatings didn’t produce complete reaction layers. AgCuInTi filler metal formed a reaction layer compsed by Ti and Si. Although the reaction layer is quite complete, but the physical property of the reaction layer may affect the joining strength.