Ga Penetration along the Grain Boundaries of Aluminum Alloys

Abstract

The Ga penetration process along grain boundaries of Al-based alloys while they are in contact with Ga containing aqueous solution was studied. It was shown that exposure in the solution at room temperature leads to the liquid Ga penetration process, which started with 3 minutes delay. The penetration rate for Al-4.7 % Zn (13 μm/s) is two times less than penetration rate in pure Al. As for Al-Cu alloys it was shown that penetration process occurs only for the alloys with 1.6 % Cu and less, but for larger value of Cu concentration Ga did not penetrate in Al. Comparison of the effect with pure Ga spreading over the alloys surface showed that the absence of penetration connected with absence of wetting.