The influence of Ti: Si3N4 ratio on the microstructure evolution of Ti–Si3N4 reaction in Cu melts

Joining of silicon nitride ceramic to oxygen‐free copper using Ag–Cu–TiH2 filler

“…Therefore, the references for analyzing the evolution of brazing liquid as the reaction proceeds are limited. It is noteworthy that the 3D morphology of Ti 5 Si 3 and/or TiN growth from the Cu‐base liquid has been reported recently in research on Cu‐base composites 22–25 . These cases are similar to the Si 3 N 4 ceramic/OFC foil joints.…”

“…Obviously, the hexagonal prism grain (point 1) is Ti 5 Si 3 according to the results of EDS and XRD analysis, which matches its D8 8 hexagonal crystal structure (P6 3 /mcm) 24,38 . Many huge Ti 5 Si 3 hexagonal prisms have a hollow core, which reportedly involves the remelting of Ti 5 Si 3 23–25 . A simple evolution process of the hollow core can be found in Figure 4 (labeled by green arrows).…”

“…It is noteworthy that the 3D morphology of Ti 5 Si 3 and/or TiN growth from the Cu-base liquid has been reported recently in research on Cu-base composites. [22][23][24][25] These cases are similar to the Si 3 N 4 ceramic/OFC foil joints. Thus, they are used as references to investigate the 3D morphology of the interfacial reaction products and to further analyze the evolution of the brazing liquid.…”

“…24,38 Many huge Ti 5 Si 3 hexagonal prisms have a hollow core, which reportedly involves the remelting of Ti 5 Si 3 . [23][24][25] A simple evolution process of the hollow core can be found in Figure 4 (labeled by green arrows).…”

“…23 Moreover, as the TiN layer generated As the reaction proceeds, the Si released from reactions (1) and ( 2) becomes saturated and reacts with Ti to form Ti 5 Si 3 , which precipitates from Cu-Ti-Si(l) and grows into regular crystals, as shown in reaction (3). As displayed in Figure 9C, two nucleation and growth mechanisms are found for Ti 5 Si 3 25,32,64 : heterogeneous nucleation with the TiN layer as the nucleation site, which then grows attached to the TiN layer; and homogeneous nucleation in Cu-Ti-Si(l), followed by sufficient growth and random moving in the brazing liquid. As a result, Ti 5 Si 3 is observed both on the interfacial reaction layer and in the brazing alloy (Figure 2).…”