| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2006: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2005: ¥2,700,000 (Direct Cost: ¥2,700,000)
|
|---|
| Research Abstract |
In this study, resistance welding was applied to the bonding of SiC to metals. The welded interface structure was observed by high-resolution transmission electron microscopy to reveal the reaction during welding. In addition, in order to reveal the mechanism of the reaction products formation during resistance welding, we applied in-situ heating HRTEM technique to SiC/molten metals reactions.
Firstly, we developed the resistance welding machine to bond the SiC to metals. The maximum bonding temperature of SiC varied with the rate of welding current rise. At the welded interface, A1_4C_3, Al and an amorphous phase were formed adjacent to SiC in the SiC/Al system. The SiC/Al interface was flat at the atomic level and the crystallographic orientation relationship between SiC and Al was observed. For the SiC/Ag-Cu-Ti alloy system, the reaction phases TiC and Ti_5Si_3 were formed at the interface. The thickness of the reaction phases varied with the rate of welding current rise, and, under specific welding conditions, Ag formed directly adjacent to SiC without the reaction phases.
The in-situ heating HRTEM technique revealed that, at the front of the spreading Ag-Cu-Ti molten alloy on the SiC substrate, TiC is formed and the Ti_5Si_3 is formed approximately 10 nm behind the front of the TiC. No habit plane is observed at the front of the TiC. In spite of the thin TiC layer region, crystallograp hic orientation relationship is observed between SiC and TiC such as (10-12)SiC//(111)TiC, [1-210]SiC//[1-10]TiC. In contrast, layer by layer growth of TiC at the front of the spreading molten alloy was also observed.
|
