Investigation of Si_3N_4 Ceramic/42CrMo Steel Joints Brazed with Ag-Cu-Ti Brazing Alloy Plus WC Particles

Yanming He ； Jie Zhang ； Chunfeng Liu

《Advances in Ceramic Science and Engineering》 2卷4期 (2013/11) Pp. 151-160

並列摘要

Active metal brazing is a widely used technique to join advanced ceramics and metals. In this research, Ag-Cu-Ti+WC composite filler was employed for the joining of Si_3N_4 ceramic and 42CrMo steel. Effect of WC particles content on the microstructure and mechanical properties of the joints was investigated. The results indicated that a continuous reaction layer was formed at the substrates/brazing alloy interface. The brazing layer was mainly composed of Ag and Cu based solid solution, in which WC particles, TiC reaction layer around WC and Cu-Ti intermetallics were randomly dispersed. The maximal bending strength could reach 320.5MPa while 15 vol.% WC particles were incorporated, in which the joint strength was 180.65% higher than the average strength for the case without WC particles addition. The following factors cooperated together to contribute the maximum: the coefficient of thermal expansion reduction of the brazing alloy, formation of Cu-Ti intermetallics, the reaction layer with a definite thickness formed at the Si3N4 ceramic/brazing alloy interface.

並列關鍵字

Si_3N_4 Ceramic ； Joining ； Inclusions ； Residual Stress ； MechnicalProperties