Identification and Microstructure Observation of Reaction Products formed at Alumina/Ag-33.5Cu-1.5Ti Brazing alloy Interface

,; ,; ,; ,

J. Korean Ceram. Soc. > Volume 33(9); 1996 > Article

Journal of the Korean Ceramic Society 1996;33(9): 1045.

알루미나의 Ag-33.5Cu-1.5Ti 브레이징 합금 계면에서 생성되는 반응층의 미세조직 관찰과 상 동정

최시경, 권순용

한국과학기술원 재료공학과

Identification and Microstructure Observation of Reaction Products formed at Alumina/Ag-33.5Cu-1.5Ti Brazing alloy Interface

ABSTRACT

Pressureless-sintered polycrystalline alumina and carbon steel were joined with Ag-33.5Cu-1.5Ti (wt%) brazing alloy. SEM observation revealed that two reaction layers with different thicknesses were continuously formed between the alumina and the brazing alloy. A thick layer formed on the brazing alloy side was identified as Ti3(Cu0.93Al0.07)3O phase with diamond cubic structure. Another thin layer adjacent to the alumina was revealed as $delta$-TiO phase of which the crystal structure was HCP with a lattice parameter of a0=0.419 nm and c0=0.284 nm. It was confirmed using XPS analysis that $delta$-TiO was formed directly by a redox reaction of alumina with titanium ir, molten brazing alloy.

Key words: Alumina, Brazing, Reaction products, $\delta$-TiO, Redox reaction