Influence of Silicon on the Wetting-Bond Strength-Structure Relationship in the AlSi11/Al2O3 Joints.

The subject of the work was to study the effect of Si alloying addition to the aluminum on the bond strength properties, wettability, and structure of interface in the AlSi11/Al₂O₃ .joints. Taking advantage of the sessile drop method, the wetting of alumina substrates by liquid AlSi11 alloy or Al was studied. The sessile drop tests were carried out in the temperature range between 1023 and 1223 K, under a vacuum of 0.2 mPa for 30 or 120 minutes of contact. The shear strength results demonstrated significant improvement of shear strength of AlSi11/Al₂O₃ joints due to the application of silicon as an alloying addition to aluminum. Microstructural investigations of interface indicated that the silicon crystals were formed at the AlSi11/Al₂O₃ interface, which influenced the strengthening of these joints. A conclusion could be drawn, that the interface structure influenced the increase of the shear strength of AlSi11/Al₂O₃ joints. [ABSTRACT FROM AUTHOR]