Microstructure and properties of an Al–Ti–Cu–Si brazing alloy for SiC–metal joining
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An Al–Ti–Cu–Si solid–liquid dual-phase alloy that exhibits good wettability and appropriate interfacial reaction with SiC at 500–600°C was designed for SiC–metal joining. The microstructure, phases, differential thermal curves, and high-temperature wetting behavior of the alloy were analyzed using scanning electron microscopy, X-ray diffraction analysis, differential scanning calorimetry, and the sessile drop method. The experimental results show that the 76.5Al–8.5Ti–5Cu–10Si alloy is mainly composed of Al–Al2Cu and Al–Si hypoeutectic low-melting-point microstructures (493–586°C) and the high-melting-point intermetallic compound AlTiSi (840°C). The contact angle, determined by high-temperature wetting experiments, is approximately 54°. Furthermore, the wetting interface is smooth and contains no obvious defects. Metallurgical bonding at the interface is attributable to the reaction between Al and Si in the alloy and ceramic, respectively. The formation of the brittle Al4C3 phase at the interface is suppressed by the addition of 10wt% Si to the alloy.
Keywordsaluminum titanium copper alloys joining ceramic–metal interfaces melting point wettability
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This work was financially supported by the High-Tech Research and Development Program of China (No. SS2013AA031305) and the Key Technologies R&D Program of Tianjin (No. 12ZCDGGX49100).
- J.G. Li, Wettability of silicon carbide by liquid silver and binary silver–silicon alloy, Mater. Lett., 18(1994, No. 5–6), 291.Google Scholar
- X.S. Cong, Wettability of Silicon Carbide by Molten Aluminum or Aluminum Alloys and Their Interfacial Microstructures [Dissertation], Jilin University, Changchun, 2014, p. 24.Google Scholar